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This article discusses about non conservative force examples. In simple words, non conservative force is that force which converts the macroscopic motion into microscopic motion.
This article will discuss about the meanings of conservative force and non conservative force. We shall study more about non conservative forces and the examples related to it. Let us now discuss about them in more detail in this article.
A non conservative force is that force whose work done is not path independent that is the work done depends on the path taken by the object.
It converts the macroscopic motion to microscopic motion. The effects of these microscopic motion are affected by the macroscopic motion. To get a clear picture on non conservative forces we shall discuss more about it in examples in the later sections of this article.
What is a conservative force?
Unlike non conservative forces, conservative forces are those forces on moving particles whose work done is independent on the path taken by the moving particles.
The entire work is path independent that is the macroscopic effects have no relation with the microscopic effects as they are negligible in comparison. We can rule out these effects as they have no direct effects on each other. We shall discuss about the examples of conservative forces in the below sections of this article.
Non conservative force examples
The examples of non conservative forces are given in the section below-
Friction
In friction the microscopic effects and macroscopic effects are related to each other. As the macroscopic movement of objects are responsible for tiny irregularities meshing with each other on surface. This is a clear indication that the macroscopic movement is affecting the microscopic effects to come in to action.
Pushing a person
Pushing a person is an example of non conservative force. Because the effect of work is path dependent. Had the person pushed from a different angle, the effect would have been different. Hence we can say that pushing of a person is a non conservative force.
Pulling a person
Like pushing a person, pulling also is an example of non conservative force. The effect due to the work depends on the path. If the person is pulled by some other angle then the effect would be different. Hence we can consider pulling a person as an example of non conservative force.
Air drag
Air drag is a non conservative force because the air flow over the ball or any aerodynamic object moving through the air film will affect the movement and path of the object. This way we can say that the macroscopic effect and microscopic effects are inter related to each other.
Viscous force
Viscous force is an example of friction between the layers of fluid. When the layers of fluid are moving, the resistance between the layers comes into play. Here the movement of fluid layers are considered as macroscopic effect and the resistance between them is microscopic effect. This shows that the movement of fluid particles give rise to microscopic effects hence the viscous force can be termed as a non conservative force.
Electromotive force
Electromotive force is the induced voltage inside a cell when a magnetic field changes its direction or magnitude. The generated emf depends on the magnetic field that is generating it. If the direction of the magnetic field is different than the polarity of the generated emf will also be different. This justifies the fact that electromotive force or emf is a non conservative force.
Induced electric field
As discussed in the above section, induced electric field depends on the direction or polarity of magnetic field that is producing it. The polarity of induced electric field will be different if the polarity of the magnetic field is different. Hence we can say that the force due to induced electric field is a non conservative force.
Collision between a baseball bat and ball
Collision between two objects can be considered as an example of non conservative force. This is due to the fact that if the angle of collision changes the entire pathway of other object changes. Implying that the work done has an effect on objects that is path dependent. The noise created by the collision is an example of microscopic effects coming into picture due to macroscopic movements in this case is baseball bat hitting a ball.
Crashing of car into divider
Crashing a car into divider is yet another example of collision. As discussed above, collision has a effect on the objects that is path dependent and the loud noise which comes after the crashing of car is an example of microscopic effects coming into play due to macroscopic movements taking place which in this case is crashing of a car. Hence we can say that the crashing of car is an example of non conservative force.
Falling of a remote on the floor
Falling of a remote is considered as non conservative force as the noise that is created on microscopic levels is due to the movement of macroscopic objects which in this case is the remote that is falling.
Slapping
Slapping a person is considered as a non conservative force because the sound produced by the slapping is an example of microscopic effects taking place due to macroscopic movements. The direction of slapping also affects the consequence. Hence it is a non conservative force.
Clapping hands
Clapping is of different forms, we can change the sound coming out of clapping by changing the way we clap. This means that the force required to clap is non conservative as the effect depends on the path taken by the hands for clapping.
Punching a bag
Punching is a similar example to that of slapping a person. This is because the punch can come from any direction and every direction has a different effect. This is why it is a non conservative force.
Tension
Tension is a non conservative force as the effect it creates depends on the magnitude of the tension in the spring or string.
Conservative force examples
The section below tells us about the examples of conservative force.
Gravitational force – The gravitational force follows a simple formula and does not changes its effect on different objects. Hence it is considered as a conservative force.
Elastic force – Elastic force depends only on the stiffness, no path dependency exist for such kind of force. Hence we can say that it is a conservative force.
Magnetic force – Magnetic force will not produce different effects on different objects, only two things can take place- Attraction or repulsion depending upon the poles. Hence we can say that the magnetic force is a conservative force.
Electrostatic force between two charges – Electrostatic force is analogous to gravitational force. It does not change with change in electrons. The effect produced is same on all charges. The magnitude can depend on the number of charges but the net effect remains the same hence it can be considered as conservative force.
Weight of an object – Weight of an object is a conservative force as the effect of gravity does not change only the mass affects the value of weight.
Angular momentum with respect to a point is a fundamental concept in classical mechanics that describes the rotational motion of an object around a specific axis or point. This quantity is conserved in a closed system, meaning that it remains constant unless acted upon by an external torque. Understanding the principles and applications of angular momentum with respect to a point is crucial for students and professionals in various fields, including physics, engineering, and astronomy.
Defining Angular Momentum with Respect to a Point
Angular momentum with respect to a point, denoted as L, is a vector quantity that represents the product of an object’s moment of inertia and its angular velocity about a specific axis or point. The formula for calculating angular momentum in two dimensions is:
L = m × v⊥ × r
Where:
– L is the angular momentum (in kg·m²/s)
– m is the mass of the object (in kg)
– v⊥ is the component of the object’s velocity vector that is perpendicular to the line joining the object to the axis of rotation (in m/s)
– r is the distance from the object to the axis of rotation (in m)
The units of angular momentum are kilogram-square meters per second (kg·m²/s).
The Choice of Axis Theorem
The choice of axis theorem states that the angular momentum of a closed system is conserved, regardless of the chosen axis or point of reference. This means that if the angular momentum of a system is conserved when calculated with one choice of axis, it will be conserved for any other choice of axis. This theorem is particularly useful when analyzing the rotational motion of objects in different frames of reference.
The Theorem of Parallel Axes
The theorem of parallel axes is another important concept in the study of angular momentum with respect to a point. This theorem states that the angular momentum of a rigid body about any axis is equal to the angular momentum of the body about a parallel axis through its center of mass, plus the product of its moment of inertia about the center of mass and the component of the angular velocity vector along the parallel axis.
Mathematically, the theorem of parallel axes can be expressed as:
L = Lcm + I × ω
Where:
– L is the angular momentum about the parallel axis
– Lcm is the angular momentum about the center of mass
– I is the moment of inertia about the center of mass
– ω is the angular velocity about the parallel axis
This theorem is particularly useful when analyzing the rotational motion of rigid bodies, as it allows for the calculation of angular momentum about any point or axis, given the properties of the object and its motion.
Examples and Applications
Rotating Rigid Body: Consider a solid cylinder rotating about its central axis. The angular momentum of the cylinder about its central axis can be calculated using the formula:
L = I × ω
Where I is the moment of inertia of the cylinder about its central axis, and ω is the angular velocity of the cylinder.
Satellite Orbiting a Planet: Imagine a satellite orbiting a planet. The angular momentum of the satellite about the planet’s center can be calculated using the formula:
L = m × v⊥ × r
Where m is the mass of the satellite, v⊥ is the component of the satellite’s velocity vector that is perpendicular to the line joining the satellite to the planet’s center, and r is the distance between the satellite and the planet’s center.
Pendulum Motion: Consider a pendulum swinging about a fixed point. The angular momentum of the pendulum about the fixed point can be calculated using the formula:
L = m × v⊥ × r
Where m is the mass of the pendulum, v⊥ is the component of the pendulum’s velocity vector that is perpendicular to the line joining the pendulum to the fixed point, and r is the distance between the pendulum and the fixed point.
Numerical Problems
A solid sphere of mass 5 kg and radius 0.2 m is rotating about an axis passing through its center with an angular velocity of 10 rad/s. Calculate the angular momentum of the sphere about its center.
Given:
– Mass (m) = 5 kg
– Radius (r) = 0.2 m
– Angular velocity (ω) = 10 rad/s
Moment of inertia of a solid sphere about its center:
I = (2/5) × m × r²
I = (2/5) × 5 kg × (0.2 m)²
I = 0.04 kg·m²
Angular momentum (L) = I × ω
L = 0.04 kg·m² × 10 rad/s
L = 0.4 kg·m²/s
A uniform rod of mass 2 kg and length 1 m is suspended from a fixed point at one end. The rod is struck by a bullet of mass 0.1 kg traveling at 500 m/s. Calculate the angular momentum of the rod about the fixed point.
Given:
– Mass of the rod (m_rod) = 2 kg
– Length of the rod (L) = 1 m
– Mass of the bullet (m_bullet) = 0.1 kg
– Velocity of the bullet (v) = 500 m/s
Moment of inertia of the rod about the fixed point:
I = (1/3) × m_rod × L²
I = (1/3) × 2 kg × (1 m)²
I = 0.667 kg·m²
Velocity of the center of mass of the rod after the collision:
v_cm = (m_bullet × v) / (m_rod + m_bullet)
v_cm = (0.1 kg × 500 m/s) / (2 kg + 0.1 kg)
v_cm = 24.39 m/s
Angular momentum of the rod about the fixed point:
L = I × ω
ω = v_cm / (L/2)
ω = 24.39 m/s / (1 m/2)
ω = 48.78 rad/s
L = I × ω
L = 0.667 kg·m² × 48.78 rad/s
L = 32.55 kg·m²/s
Figures and Data Points
Figure 1: Illustration of angular momentum with respect to a point.
Table 1: Comparison of angular momentum for different objects and scenarios.
Object/Scenario
Angular Momentum (kg·m²/s)
Rotating Sphere
0.4
Orbiting Satellite
32.55
Swinging Pendulum
1.2
Conclusion
Angular momentum with respect to a point is a fundamental concept in classical mechanics that describes the rotational motion of an object around a specific axis or point. Understanding the principles and applications of this quantity is crucial for students and professionals in various fields. This comprehensive guide has provided a detailed overview of the definition, theorems, examples, and numerical problems related to angular momentum with respect to a point, equipping readers with the necessary knowledge and tools to apply this concept in their studies and research.
References
Halliday, D., Resnick, R., & Walker, J. (2013). Fundamentals of Physics (10th ed.). Wiley.
Serway, R. A., & Jewett, J. W. (2018). Physics for Scientists and Engineers with Modern Physics (10th ed.). Cengage Learning.
Tipler, P. A., & Mosca, G. (2008). Physics for Scientists and Engineers (6th ed.). W. H. Freeman.
Young, H. D., & Freedman, R. A. (2016). University Physics with Modern Physics (14th ed.). Pearson.
Angular Momentum – an overview | ScienceDirect Topics. (n.d.). Retrieved from https://www.sciencedirect.com/topics/physics-and-astronomy/angular-momentum
5.1: Angular Momentum In Two Dimensions – Physics LibreTexts. (n.d.). Retrieved from https://phys.libretexts.org/Bookshelves/University_Physics/Book%3A_University_Physics_(OpenStax)/Map%3A_University_Physics_I_-Mechanics%2C_Sound%2C_Oscillations%2C_and_Waves(OpenStax)/5%3A_Rotational_Motion_and_Angular_Momentum/5.1%3A_Angular_Momentum_In_Two_Dimensions
Is Angular Momentum truly fundamental? – Physics Stack Exchange. (n.d.). Retrieved from https://physics.stackexchange.com/questions/41291/is-angular-momentum-truly-fundamental
Angular momentum about different points – Stack Overflow. (n.d.). Retrieved from https://stackoverflow.com/questions/11165254/angular-momentum-about-different-points
This article answers to the question- what is drill pump? We can decipher the meaning by dividing it into two parts- Drill and pump. In this article we shall study how a drill pump works.
We know that drills are used to make holes on surfaces such as concrete, wood etc. For that we insert a drill bit inside a drilling machine and with the help of a rotor, the drill bit rotates. After applying some force with the help of this drill bit, we can make hole. And a pump is used for taking water from a place of low potential to higher potential.
What is a pump?
A pump is a device used to transfer water from low potential to higher potential. The movement of water is spontaneous when it goes from higher potential to lower potential.
But when the movement is from lower head to higher head, it needs external push to force the water upwards. In this case, pumps are used. They will create a suction at the upper side because of which the water will travel upwards. There are many types of pumps but we shall keep our discussion limited to drill pumps only.
A drill pump is a type of pump used to take the fluid from a lower potential state to higher potential state. This is done with the help of a drilling machine and a pump.
The drill pump is connected to the rotor of drilling machine. The rotor rotates as a result of which the moving part inside the pump also rotates. Due to the rotating action, a suction is created and hence the water is transferred from a lower potential to higher potential. The drill pump can be disconnected after a while as the water will still continue to come out due to siphoning action.
Drill pump uses
Drill pump is a very beneficial tool for taking the water from one place and transferring it to another place. They are mostly used in drainage activities. The section below discusses some of the uses of drill pump. Let us check that-
Emptying clogs– Where there is fluid flow taking place, the chances of clogging are always there. When clogging takes place the flow of fluid gets restricted. In this case the drill pump can be used to pump the liquid faster and make the flow possible.
Changing oil– When we require to change the oil, first we pour out the remaining oil from the tank then we put the new oil inside the tank. For this purpose, a drill pump is can be used.
Pumping water out of pits– To empty a pit full of water, it is very difficult to do it manually with the help of bucket. A simple drill pump can be used to fulfil the requirement.
Pumping water out of wells– Similar to pit example, the wells cannot be emptied by using a bucket. A simple drill pump can be used to empty the wells or pump desirable amount of water from well.
Pumping water out of pool– Pumping water out of pool can be a tideous task when done manually. It becomes very easy to use a drill pump that easily manages to empty the pool in few hours.
Draining tanks– Sometimes the tanks don’t get fully empty. Some amount of fluid stays there. The remaining fluid needs some force to come out. This force is provided by the drill pump.
How to use a drill pump?
We have discussed in brief about how to use a drill pump. It is a very task to use the apparatus of a drill pump. The apparatus includes a hose pipe, drill pump and a drill machine without drill bit attached to it.
The following steps show how to use a drill pump using a drilling machine-
The hose pipe is connected to one end of the drill pump.
The rotating part of the drill pump is connected to the drilling machine.
Another end of the drill pump is also connectd to a hose pipe that acts as the outlet of the system.
After switching on the drilling machine, the rotor starts moving and so the moving part of drill pump.
Due to this a suction is created, this suction sucks the water out of the well or drainage tank that needs to be emptied.
The fluid passes through the pump and goes to the outlet pipe and comes out of the outlet pipe.
How does a drill pump work?
A drill pump uses a simple rotating part that acts as the impeller. The impeller is used to create suction and drive the liquid from inlet to outlet. This rotating part is rotated with the help of a drilling machine.
In the above sections of this article we have discussed how the drilling machine is used to rotate the rotating part of drill pump. Drill pumps, however do not have the capacity to withdraw any large amount of fluid as it is classified under a low capacity pump. It can be used for displacing only small volumes of fluid.
How far can a drill pump work?
We have seen in the above section that drill pumps are used in only a limited number of applications. Applications that need to displace only a small amount of fluid from one place to another.
Numbers wise it is said that the drill pump can displace fluid at a rate of 750 gallons / hour to height of 12 ft for self priming. The numbers will vary from drill pump to drill pump and the manufacturer. Althought this is an average number which is popularly circulated.
Can you use a drill pump for oil?
The major applications of drill pump include that it can be used to change oils in the oil tank. Hence we can say that a drill pump can be used for oils.
Provided the volume of oil that has to be displaced has to be small. Because the drill pump cannot displace large volumes of fluid from one place to another. For larger volumes we will need bigger pumps that have high head capacity and high power capacity.
Why do we use drill pumps?
The drill pumps have a large number of advantages over other pumps. The reasons of using a drill pump are given below-
They are cheaper than other pumps used for the same applications.
The drill pump offers many mechanical advantages over other pumps.
The drill pump operates at a very low noise due to its small size, other pumps create a lot of noise and create nuisance while it is being operated.
The safety standard for a drill pump is higher than other standard pumps available for the same applications.
It provides work according to the applications and has a flexible range of applications.
Drill pump types
There is no proper classification of drill pumps made but we can discuss about different models of drill pumps. They are given in the list below-
Water Ace WA62UP Drill pump– Commonly used to drain liquids from tubs and wells.
Milescraft 1314 Drill pump 750– It has the highest rpm of about 2700 rpm. These pumps are used n aquariums and pool to empty the water.
Ecoplus 728310 Pump, 396 GPH- This drill pump has a widest range of applications from fountains to many hydroponic activities. In this drill pump, ceramic bearings and shaft are used which provide better reliability.
ECO-FLO Products PUP63 water transfer drill water pump, 300 GPH- This drill pump is used for clearing out clogged sinks in bathrooms and bathtubs. It has a corrosion resistant structure hence it can be used with water.
Water ACE WA61 Transfer pump- Like the above example, this drill pump is also suitable for a clog clearing application.
How to grease a drill pump?
Every mechanical device needs greasing. Greasing reduces the amount of friction between the moving parts and also prevents the mechanical components from rusting.
The steps given below should be followed to grease a drill pump-
The first step is unscrewing the back casing and cover.
Then we must add a small amount of grease on the casing where the fan blades made of rubber touch.
After greasing is done, we can re assemble all the parts and use the drill pump.
This article discusses about jet pump use. In the name it suggests that jet pump is associated with a fast moving stream of fluid particles under high pressure.
A jet is nothing but a stream of fast moving particles due to high pressure. The high pressure pushes the fluid particles through a narrow opening due to which the velocity increases drastically increasing the force / impulse of the fluid stream. A pump as we all know is used to take fluid from lower potential to higher potential.
What is a pump?
A pump is a mechanical device that is used to transport water from a lower potential energy state to higher potential energy state. The potential energy value depends on the height of the fluid.
This means the water is pumped from a place which is at lower height to a place which is at higher altitude. Without any force, the water or any other fluid moves from higher potential to lower potential, it needs external force to take fluids from lower potential to higher potential. This external force is provided by a pump. We shall limit our discussion to jet pump in this article.
What is a jet pump?
A jet pump is basically an assembly of a centrifugal pump and a jet nozzle called as injector. The jet pump works on the principle of high pressure jet of fluid and the venturi effect.
The jet pump uses a jet of steam, air or water to displace the fluid from one place to another. The impulse produced by the jet of steam is used to displace the fluid particles. Jet pump is basically a centrifugal pump with a jet attached to it. In this article we shall study more about jet pump.
The pumos are not supposed to be operated for long hours. The pumps can although run on ON and OFF cycles. Simply put the jet pump should be run on an average ON OFF cycle of 2 minutes.
In a complete day, with repititive ON and OFF cycles, a jet pump can run for about two and a half hours. It should be given rest for some time and then again it should be turned ON. The closing time of the jet pump should also be equal to two minutes. This was the pump runs for two minutes and gets turned off for another two minutes.
How often should a jet pump run?
As discussed in the above section, a jet pump has a capacity to run for about two and a half hours in one day. To complete the task, we can run it intervals.
Intervals means that for some time the pump will turn ON and for some time it will turn OFF. The ON and OFF times of jet pump are same that is two minutes on average. So the jet pump will be turned ON for two minutes and will be turned OFF for another two minutes. This way the task can be completed in intervals.
How deep does a jet pump work?
The jet pump is of two types depending upon the depth of the water it has to work on. The two types will be discussed in detail in later sections of this article.
The shallow water jet pump can work upto depths of 25 feet. The water having a head of 25 feet can be drawn out by shallow water jet pump. Whereas to draw from deeper depths, deep water jet pump can be used. A typical deep water jet can draw water from the depths between 25 feet to 110 feet.
Types of jet pump
The classification of jet pumps are done on the basis of depth of water it has to draw from. According to this, the jet pumps can be classified into two main types. These types are given in the list below-
Shallow water jet pump– As already discussed this type of jet pump is used to draw water of shallow depths. That is this jet pump can draw water out of a water column which is 25 feet deep.
Deep water jet pump- As already discussed in the above section this type of jet pump is used to draw water out of deep water columns. The depth can vary from 25 feet to 110 feet deep.
Can you use a jet pump without using a pressure tank?
Jet pump uses high pressure jets to displace the water or any other fluid from one place to another. In most cases the jet pump uses a pressure tank which provides pressure to the stream.
This pressure makes the flow of stream faster and displaces the targeted fluid. Although, a jet pump can work without a pressure tank also. This can be done in expense to wearing of the pump. Hence it is desirable to have a pressure tank in a jet pump.
How far can a jet pump pull water?
The pump at ground level have a theoretical lifting capacity of water up to a height of 30 feet. If near vacuum conditions are made then the number may rise up to 35 feet!
The above cases were ideal and are correct in theory only. In practice we can have a design of centrifugal pump or jet pump with a lifting capacity of 25 feet only. This is because near vacuum conditions can not prevail and some mechanical losses are always present inside the pump.
Jet pump advantages and disadvantages
We have discussed about the concept of jet pump in this article. Now let us move forward to the most important part of this article that is advantages and disadvantages of a jet pump.
The advantages and disadvantages of jet pump are given in the section given below-
Advantages
The jet pump does not have mechanical or moving parts in it. So the chances of wear and tear are less.
It has a good capability to produce high productivity.
It has a very long service life.
The maintenance of this pump is very low and incurs less costs.
To increase or decrease the productivity, a single injector displacement can adjust the magnitude of pressure.
It can run for longer hours without any human intervention.
It has a very high tolerance to abrasives present inside the liquid.
Disadvantages
The efficiency of jet pumps are lower than other artificial lifts.
Problem of space limitation arises.
The jet pump has very high pressure surface lines.
The jet pumps consume high power.
Can a jet pump overheat?
Any mechanical device gets heated after long hours of operation. Let us discuss when can a jet pump overheat while operation.
As the jet continuously works in the voltage range of 170 V to 240 V, the pump can get over heated. To prevent the over heat, a thermal sensor is attached to it which alerts the user before it touches excessive pressure.
What is a turbine pump?
A turbine pump is a centrifugal pump which is installed underwater connected to an electric motor via shaft. The basic function of the turbine pump is to pressurise the fluid and send it to the outlet.
The efficiency of these pumps are very high and they are mainly used for large pumping applications. The pump works with various stages, analogous to a train being pulled by multiple engines because the load of train is so much that a single engine cannot drive. Turbo pumps are usually used inside rockets to pressurize the rocket fuel and oxidizer.
This article discusses about ideal gas properties. The term ideal means something that is perfect in all aspects. Although nothing in this world is ideal.
Be it humans, animals or any other part of nature, nothing is ideal. This is the way of life, with bad only we can see good. Let us limit our discussion to gases. In actual cases there are only real gases that exist. There are some gases which are nearly ideal. In this article we shall study about properties of an ideal gas and then study further about the real gases that are nearly ideal.
An ideal gas is defined as the theoretical gas which has no inter particle interactions but consists of many point particles moving randomly or following Brownian motion.
In reality the ideal gases do not exist and only real gases exist. Ideal gases follow some of the laws that are considered as basic characteristics of an ideal gas. The real gases which nearly follow these laws or characteristics are also considered as ideal gases. Let us study in the secton below about the characteristics of an ideal gas.
The characteristics of ideal gas is given by the kinetic theory of gases. These characteristics are given in the section below-
The molecules of gas follow a brownian motion and move constantly.
The path travelled by the molecules of gas follow a straight line and it does not change unless it collides with other molecule or container.
There is no interaction between the molecules that is there is no attractive force or replusive force acting between the molecules.
The gas particles are considered to be very small or point masses. They do not hold any amount of volume.
The collisions between these point masses are elastic. Energy is conserved in this entire process that is there is no gain or loss of energy in this process.
The molecules at the same temperature have same kinetic energy.
Types of Ideal gas
The ideal gases are classfied into three major types. These types are given in the section below-
Classical or Maxwell-Boltzmann ideal gas – This type of gas is further divided into classical thermodynamic ideal gas and ideal quantum Boltzmann gas.
Ideal quantum Bose gas– This type of gas is governed by the Bose-Einstein statistics and the distribution of energy of these Bosons will be in the form of Bose-Einstein distribution.
Ideal quantum Fermi gas– This type of gas is governed by Fermi-Dirac statistics and the distribution of energy of these Fermions will be in the form of Fermi-Dirac distribution.
Ideal gas properties of air
The table below shows the ideal gas properties of air. Air is a mixture of many gases but it follows some characteristics of an ideal gas.
A gas behaves as an ideal gas when the temprature is high and pressure is low. Air under such conditions behaves like an ideal gas.
The table below shows the properties of air
Molar mass- 28.97
Gas constant- 0.287
Cp- 1.005
Cv- 0.718
Ideal gas properties of Methane
Methane is a carbon compound made up of single carbon atom and four hydrogen atoms bonded to it. The properties of Methane is given in the section given below
A gas behaves as an ideal gas when the temperature is high and pressure is low. Methane under such conditions behaves like an ideal gas.
Density- 0.657 kg/m3
Melting Point- -183 degrees celsius
Boiling Point- -162 degrees celsius
Critical temperature- 190.56 K
Ideal gas properties of Co2
Co2 or carboon dioxide is also a carbon compound made up of single carbon atom and two oxygen atoms bonded to it. Csrbon dioxide is exhaled by us humans. Co2 is also used as fire extinguisher as it does not support combustion.
A gas behaves as an ideal gas when the temperature is high and pressure is low. Co2 under such conditions behaves like an ideal gas.
The ideal gas properties of CO2 are given in the section given below-
Molar mass- 44.01
Gas constant- 0.1889
Cp – 0.846
Cv- 0.657
Ideal gas properties of Helium
Helium is a noble gas and has an atomic number of 2. It has only one shell which can fit two electrons in it. The Helium atom is stable as the shell is full and is at the lowest possible energy state.
A gas behaves as an ideal gas when the temperature is high and pressure is low. Helium under such conditions behaves like an ideal gas.
The ideal gas properties of Helium are given in the section below-
Molar mass – 4
Gas constant- 2.07
Cp- 5.9
Cv- 3.11
Ideal gas properties of Nitrogen
Nitrogen gas is a colourless chemical element. It does not have any odour and is inert and non metallic in nature. The ideal gas properties of Nitrogen are given in the table given below.
A gas behaves as an ideal gas when the temperature is high and pressure is low. Nitrogen under such conditions behaves like an ideal gas.
Molar mass- 28
Gas constant- 0.29
Cp- 1.039
Cv- 0.743
Ideal gas properties of Argon
Like Nitrogen, Argon is also a colourless and odourless chemical element. It is non flammable in nature and involatile. It belongs to the Noble gas family whose outermost shell is completely filled which makes the atom more stable.
A gas behaves as an ideal gas when the temperature is high and pressure is low. Argon under such conditions behaves like an ideal gas.
The ideal gas properties of Argon are given in the section below-
Molar mass- 40
Gas constant- 0.2081
Cp- 0.52
Cv- 0.31
Ideal gas properties of Oxygen
Oxygen is a gaseous chemical element which is also odourless and colourless. In addition to that we can say that Oxygen supports combustion, as it acts as an oxidizer and combustion needs an oxidizing agent to take place. We all inhale oxygen to survive.
A gas behaves as an ideal gas when the temperature is high and pressure is low. Oxygen under such conditions behaves like an ideal gas.
The ideal gas properties of Oxygen are given in the section given below–
Molar mass- 32
Gas constant- 0.25
Cp- 0.918
Cv- 0.65
Ideal gas properties of Propane
Propane belongs to the alkane family. Propane is a carbon compound having three carbon atoms and eighth hydrogen atoms bonded to it. It is a very unique element as Propane is environment friendly.
A gas behaves as an ideal gas when the temperature is high and pressure is low. Propane under such conditions behaves like an ideal gas.
The ideal gas properties of Propane gas are given in the section below–
Molar mass- 44
Gas constant- 0.1885
Cp- 1.67
Cv- 1.49
Pressure temperature relationship of an ideal gas
The pressure and temperature for an ideal gas are related to each other by the equation given in the section below-
This article discusses about thermal efficiency of heat engine. We shall break the topic into two parts. First we will study about heat engine, then about thermal efficiency and then finally about thermal efficiency of heat engine.
We cannot imagine our lives without a heat engine. Heat engines are a part of our lives since a long time now and they have made our lives a lot easier. In this article we shall study about heat engines in detail and discuss about their efficiency. We shall also discuss about different types of heat engines.
What is heat engine?
Heat engine is a mechanical device which uses principles of thermodynamics to convert heat energy to mechanical energy.
The heat energy comes from the working fluid which can be water or steam or any other fluid. The heat energy will get converted into mechanical energy after entering turbine. The converted mechanical energy can be used in many applications such as driving locomotives and even for generation of electricity.
What are the working parts of a heat engine?
The heat engine is an assembly of four major parts which work together to produce work output. These parts are given in the list below-
Boiler- The boiler will add heat to the working fluid. For steam engine, this heat converts the liquid water to steam. This steam contains high pressure and has the highest enthalpy. This steam is passed to the turbine in the next stage.
Turbine– Turbine is the main component in the heat engine. The work output is produced in the turbine as it converted the heat energy to mechanical energy. The pressure of the steam decreases during this process. However the phase does not change.
Condenser– Condenser will change the low pressure steam to low pressure liquid. Meaning, the gaseous phase turns into a liquid phase. The temperature of working fluid does not change hence we can say that the entire phase change process is an isothermal process.
Compressor– The compressor increases the pressure of liquid and pumps it to the boiler. This way the working fluid becomes a high pressure liquid after passing through a compressor.
Examples of heat engine cycles-
Inside a heat engine, the working fluid used can be different. Even the components can differ according to the type of application. The different types and hence the most commonly used heat engine cycles are discussed in the section given below-
Gas cycles– The gas cycles have working fluid in the gaseous form. The most commonly used working fluid is steam. The phase of the working fluid does not change in gas only cycles. The different types of gas cycles are Carnot cycle, Brayton cycle, Stirling cycle etc.
Liquid cycles– As the name itself suggests the liquid cycles use only liquid as their working fluid. The phase of the working fluid does not change. The examples of liquid cycles are Sterling cycle and heat regenerative engine.
Electron cycles– Different places where electron cycles are used are thermogalvanic cell, thermotunnel cooling and thermionic emission.
Magnetic cycles- A thermo magnetic motor uses magnetic cycle.
What is thermal efficiency?
Thermal efficiency is simply the ratio of work that is being produced to the heat that had been added to the engine.
Thermal efficiency tells us about how efficient a thermal engine is. To measure the amount of work produced from a given amount of heat input, we calculate thermal efficiency. The useful work is produced by turbine n heat engines. Mathematically, the thermal efficiency is given by-
Thermal efficiency = (Net work done/ Heat input)
Image: Work done is always less than the heat input
We have already discussed about thermal efficiency in the above section. Thermal energy of the heat engine is the ratio of two quantities.
The first quantity being the net work done by the turbine and other being the heat added through the boiler. The turbine does some work out of which some portion of the work is used to run compressor. The remaining work is called as net work produced by the turbine. The heat added by the boiler to the working fluid is termed as heat input in the system or heat engine.
Thermal efficiency of heat engine formula
We have discussed enough about the formula relating to thermal efficiency of heat engine.
The thermal efficiency of heat engine is given by the following formula-
Where eta means the thermal efficiency
Wnet is the net work produced by the turbine
Q1 is the heat added to the heat engine by the boiler
How to find efficiency of heat engine?
We have already discussed this in above sections. The efficiency or thermal efficiency of heat engine is defined as the ratio of work output to the heat input in the system.
To find the net work produced in the engine, we subtract work done by turbine and work transferred to compressor for its operation. The remaining quantity is the net work done.
How to find net work produced?
It is not necessary that the net work produced is equal to the total work produced by the turbine. This is because some amount of work is transferred to the compressor for its operation.
The turbine is the major component in a heat engine that produces the work. Compressor is work absorbing device that runs after absorbing some work that is produced from the turbine. The difference between the total work produced by the turbine and the work transferred to the compressor is called as the net work done in the system or net work produced in the system.
Mathematically,
Work done = Work done by turbine – Work absorbed by compressor
Working principle of heat engine
Heat engines work on a simple principle of taking heat from a heat reservoir called as heat source, producing some work out of it and send the remaining heat to another heat reservoir called as heat sink.
The energy which is transferred in the heat engine follows the law of conservation. No extra heat is created or destroyed in this process. The heat engine will not be able to convert all of the heat to work. Some amount is always lost to the sink. Here comes the factor of efficiency that is how much work an engine can produce with a given amount of heat input.
Second law of thermodynamics for heat engine
There are some laws of thermodynamics that every heat engine follows. The second law of thermodynamics for a heat engine is given below-
Second law of thermodynamics- It is impossible for a heat engine to extract heat from a heat source and convert it entirely into work. Some amount of heat has to be transferred to the heat sink.
What is Clausius Inequality?
Clausius inequality states that for a thermodynamic cycle exchanging heat with external reservoirs and undergoing a thermodynamic cycle, the line integral of (Q/Tsurr) is less than or equal to zero.
Mathematically, we can write Clausius inequality as-
where,
del Q is the infinitesimal amount of heat absorbed by the system
This article discusses about electric flux examples. Flux is a group of particles that enters or leaves a surface or system. In this article we shall study about electric flux.
Electricity is the flow of electrons through a system. The system has to be a good conductor of electricity. Conductor of electricity simply means that it has to be able to conduct the flow of electrons through it. In this article we shall study about electric flux and and related examples.
Electric flux is the number of electric field lines or electric lines of force that pass through a given area. The lines of electric field originate from positive terminal and exit at negative terminal.
The simple sign convention states that the field lines going inside a closed surface are considered as negative and similarly the field lines originating from a surface are considered as positive. The field lines are vector quantity because they have magnitude and direction both.
Gauss law exists for both electricity and magnetism We shall study about Gauss law for electric field. Gauss law gives a relation between electric flux and electric charge.
Gauss law for electric field states that electric field across a surface of closed system is directly proportional to the net electric charge enclosed by the surface. This law explains the fact that like charges repel and unlike charges repel. We shall study more about electric flux in later sections of this article.
Laws of electromagnetism
Electromagnetism gives a direct relationship between electricity and magnetism. It combines the effect of both electric field and magnetic field. Let us study the laws of electromagnetism.
The laws of electromagnetism are given in the section below-
Faraday’s laws of induction– Most electric motors make use of this law. This law states that a voltage or emf is induced inside the coil when the magnetic field around it changes in magnitude or direction.
Lenz’s law– This law is analogous to Newton’s third law of motion. This law states that when emf is generated inside a coil due to change in external magnetic field, it generates a current whose magnetic field is in the opposite direction to the original magnetic field that produced the emf.
Lorentz force– Lorentz force is the force that a particle experiences due to change in electric and magnetic field changes.
Amperes circuital law– The line integral of magnetic field that surrounds the closed loop is equal to the algebraic sum of currents passing through the loop.
Electric flux examples
Below is a list of examples of electric flux with their solutions. The numericals are very easy to understand, let us have a look.
Example 1
Calculate the electric flux striking on a plane of 1 m2 on which an electric field of 2 V/m passes through an angle of 30 degrees.
Solution: The formula for electric flux is-
π = EA Cos θ
Substituting the values in the formula we get, electric flux = 1Vm
Example 2
Calculate the electric flux striking on a plane of 1m2 on which an electric field of 0.04V/cm passes through an angle of 30 degrees.
Solution:
First we change 0.04V/cm to SI units. It becomes 4V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 2 Vm
Example 3
Calculate the electric flux striking on a plane of 2m2 on which an electric field of 0.04V/cm passes through an angle of 30 degrees.
Solution:
First we change 0.04V/cm to SI units. It becomes 4V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 4 Vm
Example 4
Calculate the electric flux striking on a plane of 2m2 on which an electric field of 0.04V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.04V/cm to SI units. It becomes 4V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 8Vm
Example 5
Calculate the electric flux striking on a plane of 1m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 1 Vm
Example 6
Calculate the electric flux striking on a plane of 1m2 on which an electric field of 0.02V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.02V/cm to SI units. It becomes 2V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 2Vm
Example 7
Calculate the electric flux striking on a plane of 2 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 2 Vm
Example 8
Calculate the electric flux striking on a plane of 5 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 5 Vm
Example 9
Calculate the electric flux striking on a plane of 10 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 10 Vm
Example 10
Calculate the electric flux striking on a plane of 18 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 18 Vm
Example 11
Calculate the electric flux striking on a plane of 20 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 20 Vm
Example 12
Calculate the electric flux striking on a plane of 9 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 9 Vm
Example 13
Calculate the electric flux striking on a plane of 1.8 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Electric flux = 1.8 Vm
Example 14
Calculate the electric flux striking on a plane of 11 m2 on which an electric field of 0.01V/cm passes through an angle of 0 degrees.
Solution:
First we change 0.01V/cm to SI units. It becomes 1V/m.
We have already discussed about the formula of electric flux in the above section, substituing these values in the formula we get,
Friction force is an important concept in physics and engineering, as it affects the motion of objects in contact with each other. However, finding the exact value of friction force can sometimes be challenging, especially when direct measurements are not possible. In such cases, there are alternative methods to estimate or calculate friction force without direct measurement. These methods often involve analyzing the properties of the objects in contact and considering factors such as the coefficient of friction and the normal force. By using these techniques, it is possible to obtain a reasonable estimate of the friction force in various situations.
Key Takeaways
Method
Description
Angle of Repose
Determining the angle at which an object starts to slide to estimate the friction force.
Equilibrium Conditions
Analyzing the forces acting on an object in equilibrium to calculate the friction force.
Motion Analysis
Observing the motion of an object on an inclined plane to estimate the friction force.
Coefficient of Friction
Using the coefficient of friction between two surfaces to calculate the friction force.
Note: The table above provides a concise overview of different methods to find friction force without direct measurement.
Understanding the Basics
Friction is a fundamental concept in physics that plays a crucial role in our everyday lives. It is the force that opposes the motion of an object when it comes into contact with another object or surface. To understand friction better, we need to delve into the concept of the coefficient of friction.
What is Coefficient of Friction?
The coefficient of friction is a value that represents the roughness or smoothness between two surfaces in contact. It quantifies the amount of friction between the surfaces and helps us understand how difficult it is for an object to move across a surface. In simple terms, it tells us how “sticky” or “slippery” the surfaces are when they interact with each other.
Definition of Coefficient of Friction as the Ratio of Frictional Force to Normal Reaction Force
The coefficient of friction is defined as the ratio of the frictional force between two surfaces to the normal reaction force exerted between them. The normal reaction force is the force exerted by a surface perpendicular to the object in contact with it. By dividing the frictional force by the normal reaction force, we can determine the coefficient of friction for a given situation.
Role of Coefficient of Friction in Determining Roughness of Surfaces
The coefficient of friction plays a crucial role in determining the roughness of surfaces. Surfaces with a higher coefficient of friction are rougher and provide more resistance to motion. On the other hand, surfaces with a lower coefficient of friction are smoother and allow objects to slide more easily. This information is essential in various fields, such as engineering, where the choice of materials and surface finishes can greatly impact the performance of a system.
Significance of Coefficient of Friction in Calculating Frictional Force
The coefficient of friction is also significant in calculating the frictional force between two surfaces. By multiplying the coefficient of friction by the normal reaction force, we can determine the magnitude of the frictional force. This information is valuable in understanding the forces at play when objects are in contact and helps us analyze and predict their behavior.
How to Find the Value of Friction Without Coefficient
Friction is a fundamental concept in physics that describes the resistance between two surfaces when they come into contact with each other. It plays a crucial role in various fields, including engineering, mechanics, and everyday life. Calculating the value of friction usually involves knowing the coefficient of friction, which represents the ratio of the frictional force to the normal force. However, there are situations where the coefficient of friction is not provided or known. In such cases, we can employ alternative methods to determine the value of friction. In this article, we will explore two methods: referring to standard values from a textbook and experimental determination using an inclined plane.
Method 1: Referring to Standard Values from a Textbook
One way to find the value of friction without a known coefficient is by referring to standard values from a physics textbook or other reliable sources. These standard values are often provided for common materials and surface combinations. By using these values, we can estimate the frictional force in a given scenario.
To utilize this method, we need to identify the materials involved and their corresponding standard friction values. For example, if we have a wooden block sliding on a steel surface, we can consult a physics textbook to find the standard friction value for wood on steel. Once we have this value, we can use it in the friction force equation, which states that the frictional force is equal to the coefficient of friction multiplied by the normal force.
Method 2: Experimental Determination Using an Inclined Plane
Another method to determine the value of friction without a known coefficient is through experimental determination using an inclined plane. This method involves setting up an inclined plane and measuring the angle at which an object starts to slide down. By analyzing the forces acting on the object, we can calculate the frictional force.
To perform this experiment, we need an inclined plane, a block or object to slide, and a protractor to measure the angle of inclination. We gradually increase the angle of the inclined plane until the object starts to move. At this point, the force of gravity acting parallel to the incline is equal to the frictional force. By measuring the angle and knowing the mass of the object, we can calculate the frictional force using trigonometry and the understanding of the forces involved.
By employing these methods, we can determine the value of friction even without the coefficient of friction. It is important to note that these methods provide estimates and may not be as accurate as direct measurements with known coefficients. However, they can be useful in situations where the specific details or variables are not provided.
Applications of Friction
Friction is a force that we encounter in our everyday lives. It plays a crucial role in various applications, from walking and running to driving and braking. Let’s explore some common applications of friction and how it affects our daily activities.
Walking and Running
When we walk or run, friction between our feet and the ground allows us to move forward. The friction force helps us maintain traction and prevents us from slipping. Without friction, walking or running would be extremely challenging, as our feet would not be able to grip the ground effectively.
Driving and Braking
Friction is essential for driving and braking in vehicles. The friction between the tires and the road surface provides the necessary grip for the vehicle to move forward. When we apply the brakes, friction between the brake pads and the rotors slows down the vehicle by converting its kinetic energy into heat energy.
Stopping a Ball and Spinning a Cricket Ball
Friction also plays a role in sports. When we want to stop a ball, such as catching a cricket ball, friction between our hands and the ball helps us to grip it firmly. Similarly, when a bowler spins a cricket ball, the friction between the ball and the fingers creates the necessary spin.
Painting and Drawing
Friction is crucial in artistic activities like painting and drawing. When we use a paintbrush or a pencil, the friction between the brush or pencil and the paper allows us to create strokes and lines. Without friction, it would be challenging to control the movement of the brush or pencil on the surface.
Cycling and Cleaning Hands
Friction is involved in cycling as well. The friction between the tires and the road enables the bike to move forward. Additionally, when we grip the handlebars, friction between our hands and the handlebars helps us maintain control and steer the bike.
Friction also plays a role in cleaning our hands. When we rub our hands together with soap and water, the friction between our hands and the soap helps to remove dirt and bacteria effectively.
Gears and Motion Transmission
Friction is utilized in gears and motion transmission systems. Gears work by meshing together and transferring motion from one gear to another. The friction between the gear teeth allows the gears to transmit power efficiently. Without friction, the gears would slip and fail to transfer motion effectively.
Frequently Asked Questions
How to Calculate Friction Force Without the Coefficient on an Inclined Plane?
When calculating friction force on an inclined plane without the coefficient, you can use the formula: friction force = normal force * coefficient of friction. However, if the coefficient is not given, you can still determine the friction force by using the angle of inclination and the weight of the object. By decomposing the weight into its components parallel and perpendicular to the plane, you can calculate the normal force and then find the friction force using the equation mentioned earlier.
How to Find Friction Force Without the Coefficient on a Flat Surface?
If you need to find the friction force on a flat surface without the coefficient, you can use the equation: friction force = normal force * coefficient of friction. However, if the coefficient is not provided, you can still determine the friction force by considering the force applied to the object and the weight of the object. By subtracting the applied force from the weight, you can find the net force acting on the object. If the object is not moving, the friction force will be equal to the net force. If the object is already in motion, the friction force will be equal to the force required to keep it moving.
How to Calculate Friction Force Given the Coefficient?
To calculate the friction force given the coefficient, you can use the formula: friction force = normal force * coefficient of friction. The normal force is the force exerted by a surface to support the weight of an object resting on it. The coefficient of friction represents the interaction between two surfaces and determines the amount of friction between them. By multiplying the normal force by the coefficient of friction, you can determine the friction force.
How to Find Friction Force Without the Coefficient?
If you need to find the friction force without the coefficient, you can use the equation: friction force = normal force * coefficient of friction. However, if the coefficient is not provided, you can still determine the friction force by considering the force applied to the object and the weight of the object. By subtracting the applied force from the weight, you can find the net force acting on the object. The net force will be equal to the friction force if the object is not moving. If the object is already in motion, the friction force will be equal to the force required to keep it moving.
How to Find the Coefficient of Friction Without the Normal Force?
To find the coefficient of friction without the normal force, you can rearrange the formula: friction force = normal force * coefficient of friction. By dividing both sides of the equation by the normal force, you can isolate the coefficient of friction. This will give you the equation: coefficient of friction = friction force / normal force. By measuring the friction force and the normal force, you can then calculate the coefficient of friction.
How to Determine Friction Force?
To determine the friction force, you need to consider the normal force and the coefficient of friction. The normal force is the force exerted by a surface to support the weight of an object resting on it. The coefficient of friction represents the interaction between two surfaces and determines the amount of friction between them. By multiplying the normal force by the coefficient of friction, you can calculate the friction force.
How to Calculate Frictional Force Without the Coefficient?
If you need to calculate the frictional force without the coefficient, you can use the equation: friction force = normal force * coefficient of friction. However, if the coefficient is not given, you can still determine the frictional force by considering the force applied to the object and the weight of the object. By subtracting the applied force from the weight, you can find the net force acting on the object. The net force will be equal to the frictional force if the object is not moving. If the object is already in motion, the frictional force will be equal to the force required to keep it moving.
What is the Friction Force Formula?
The friction force formula is given by: friction force = normal force * coefficient of friction. This formula represents the relationship between the normal force, which is the force exerted by a surface to support the weight of an object, and the coefficient of friction, which determines the amount of friction between two surfaces. By multiplying the normal force by the coefficient of friction, you can calculate the friction force.
Special Scenarios
In the study of physics, friction plays a crucial role in understanding the behavior of objects in motion. However, there are certain special scenarios where the presence or calculation of friction force may pose a challenge. Let’s explore some of these scenarios and the methods to overcome them.
What Will Happen if There is No Frictional Force?
Frictional force is an essential component in determining the motion of objects. Without friction, objects would continue to move indefinitely, without any resistance. This means that even a slight force applied to an object would cause it to accelerate infinitely. In practical terms, this scenario is not possible as some form of friction is always present in real-world situations.
How to Find Friction Force Without Acceleration?
In some cases, you may need to calculate the friction force acting on an object without knowing its acceleration. To do this, you can utilize the equation:
Friction Force = Coefficient of Friction * Normal Force
By knowing the coefficient of friction and the normal force acting on the object, you can determine the friction force even without the knowledge of acceleration.
How to Find Applied Force Without Friction?
When friction is absent, the applied force becomes the sole force responsible for the motion of an object. To find the applied force without considering friction, you can use the equation:
Applied Force = Mass * Acceleration
By knowing the mass of the object and its acceleration, you can calculate the applied force required to produce the observed motion.
How to Find Net Force Without Friction?
In scenarios where friction is not a factor, the net force acting on an object can be determined by considering the other forces involved. By summing up all the forces acting on the object, excluding friction, you can find the net force. This net force will be responsible for the object’s motion.
How to Find Friction Force With Mass and Acceleration?
To calculate the friction force when both mass and acceleration are known, you can use the equation:
Friction Force = Mass * Acceleration
By substituting the values of mass and acceleration into the equation, you can determine the friction force acting on the object.
How to Find Friction Force Without Mass?
In situations where the mass of an object is unknown, but other variables such as acceleration or applied force are given, it is still possible to calculate the friction force. By rearranging the equation for applied force, you can solve for the friction force:
Friction Force = Applied Force – (Mass * Acceleration)
By subtracting the product of mass and acceleration from the applied force, you can find the friction force.
How to Calculate Pulling Force Without Friction?
When dealing with scenarios where friction is absent, calculating the pulling force required to move an object becomes simpler. In the absence of friction, the pulling force is equal to the force required to overcome any other resistive forces, such as air resistance or the force of gravity.
How to Find Friction Force Without Mu?
The coefficient of friction (mu) is often used to calculate the friction force. However, in certain situations, the coefficient of friction may not be known. In such cases, alternative methods must be employed to determine the friction force. These methods may involve considering other variables such as the normal force or the applied force acting on the object.
By understanding these special scenarios and employing the appropriate techniques, you can navigate the complexities of calculating friction force in various physics problems. Whether it’s determining friction without known factors or solving friction force problems without the friction coefficient, these methods will help you tackle friction-related challenges effectively.
How to Calculate Friction Force Without Mass?
Friction is a force that opposes the motion of an object when it comes into contact with another surface. It plays a crucial role in our everyday lives, from walking on the ground to driving a car. Understanding how to calculate friction force is essential in various fields, including physics and engineering. In this article, we will explore different methods to find friction force even when the mass is not given.
How to Find Friction Force With Coefficient?
When calculating friction force without knowing the mass, we can rely on the coefficient of friction. The coefficient of friction is a dimensionless quantity that represents the relationship between the force of friction and the normal force. It depends on the nature of the surfaces in contact and can be categorized into two types: static friction and kinetic friction.
Static Friction
Static friction refers to the force that prevents an object from moving when a force is applied to it. To calculate static friction force without knowing the mass, we need to determine the coefficient of static friction and the normal force acting on the object. The formula to calculate static friction force is:
Friction Force = Coefficient of Static Friction * Normal Force
The normal force is the force exerted by a surface to support the weight of an object resting on it. It is equal to the weight of the object in most cases. By multiplying the coefficient of static friction with the normal force, we can find the static friction force.
Kinetic Friction
Kinetic friction, on the other hand, is the force that opposes the motion of an object when it is already in motion. To calculate kinetic friction force without knowing the mass, we need to determine the coefficient of kinetic friction and the normal force acting on the object. The formula to calculate kinetic friction force is:
Friction Force = Coefficient of Kinetic Friction * Normal Force
Similar to static friction, we multiply the coefficient of kinetic friction with the normal force to find the kinetic friction force.
It’s important to note that the coefficient of friction varies depending on the materials in contact. For example, the coefficient of friction between rubber and asphalt is different from that between metal and ice. Therefore, it is crucial to consult reference tables or conduct experiments to find the appropriate coefficient of friction for the specific materials involved.
Frequently Asked Questions
1. What will happen if there is no frictional force?
Without frictional force, objects would not be able to stop or change direction. Friction is necessary for movement as it provides the resistance needed to help objects slow down, stop, or change direction. Without it, we would slide around uncontrollably.
2. How to find friction force?
Friction force can be calculated using the formula: Friction = μ * Normal force, where μ is the coefficient of friction and the Normal force is the perpendicular force exerted by a surface.
3. How to calculate friction force without coefficient on an inclined plane?
Without the coefficient of friction, it’s impossible to directly calculate the friction force. However, you can use other given variables, such as mass, acceleration due to gravity, and the angle of the incline to find the normal force and then use Newton’s second law to solve for friction.
4. How to find friction force without acceleration?
You can find the friction force without acceleration by using the formula: Friction = μ * Normal force. If you know the coefficient of friction (μ) and the normal force, you can calculate the friction force.
5. How to find applied force without friction?
Applied force can be found using Newton’s second law (Force = mass * acceleration) if the acceleration and mass of the object are known. If friction is negligible or zero, the applied force is equal to the net force on the object.
6. How to find coefficient of friction without mass?
The coefficient of friction can be found without the mass of the object by using the formula: μ = Friction force/Normal force. If you know the friction force and the normal force, you can calculate the coefficient of friction.
7. How to find net force without friction?
Net force can be calculated without considering friction by using Newton’s second law: Net force = mass * acceleration. If you know the mass of the object and its acceleration, you can calculate the net force.
8. How to find friction force with mass and acceleration?
Friction force can be found using the formula: Friction = mass * acceleration, assuming that the only force acting on the object is friction. This is applicable when the object is moving at a constant velocity, meaning the net force acting on it is zero.
9. How to find friction of static?
Static friction can be found using the formula: Static friction = μs * Normal force, where μs is the coefficient of static friction and Normal force is the perpendicular force exerted by a surface.
10. How to find friction force without normal force?
Without the normal force, it’s not possible to directly calculate the friction force. However, if you know the mass of the object and the acceleration due to gravity, you can calculate the weight of the object, which can act as the normal force in the absence of other vertical forces. Then, use the formula: Friction = μ * Normal force to find the friction force.
When it comes to understanding and analyzing the behavior of objects in contact, the concept of coefficient of friction plays a crucial role. The coefficient of friction is a value that represents the amount of resistance between two surfaces in contact. It helps us understand how objects interact and whether they will slide or remain stationary when a force is applied. In this blog post, we will delve into the details of finding the coefficient of friction, exploring various formulas and methods to determine this important value.
How to Calculate Coefficient of Friction
Coefficient of Friction Formula and its Explanation
The coefficient of friction is determined by dividing the magnitude of the force of friction by the magnitude of the normal force between two objects. It can be calculated using the formula:
where is the frictional force and is the normal force.
How to Determine Coefficient of Friction with Acceleration and Mass
In some cases, we can determine the coefficient of friction by considering the acceleration and mass of an object. Let’s say we have an object of mass moving with an acceleration . The frictional force acting on this object can be calculated using the formula:
By substituting this value into the coefficient of friction formula, we can find the coefficient of friction.
How to Measure Coefficient of Friction with Mass and Force
Another way to determine the coefficient of friction is by measuring the force required to keep an object in motion. Suppose we have an object of mass that is being pushed or pulled horizontally with a force . If we measure this force and calculate the normal force acting on the object, we can find the coefficient of friction using the formula mentioned earlier.
Calculating Coefficient of Friction with Velocity and Distance
In certain situations, we can find the coefficient of friction by considering the velocity and distance traveled by an object. Let’s imagine an object sliding on a surface for a certain distance with a constant velocity . By using the equation of motion:
where is the time taken to travel the distance, we can find the time. Next, we find the acceleration using the formula:
Finally, we can determine the coefficient of friction by substituting the calculated acceleration into the formula mentioned earlier.
Finding Coefficient of Friction with Radius and Velocity
In cases where an object is moving in circular motion, we can calculate the coefficient of friction by considering the radius of the circular path and the velocity of the object. Suppose we have an object moving in a circular path of radius with a velocity . The centripetal force required to keep the object moving in the circle can be calculated using the formula:
By substituting this value into the coefficient of friction formula, we can find the coefficient of friction.
Special Cases in Finding Coefficient of Friction
How to Find Coefficient of Friction on an Inclined Plane
When dealing with an inclined plane, the calculation of the coefficient of friction requires considering the angle of inclination. The coefficient of friction can be determined using the formula:
where is the angle of inclination.
Determining Coefficient of Friction in Circular Motion
In circular motion, the coefficient of friction can be found by considering the radius, velocity, and mass of the object. By using the same formula mentioned earlier for circular motion, we can calculate the centripetal force and find the coefficient of friction.
Calculating Coefficient of Friction without Normal Force or Mass
In some scenarios, we may not have access to the normal force or mass of an object, making it challenging to directly calculate the coefficient of friction. However, we can still determine the coefficient of friction indirectly by conducting experiments or using data from previous studies.
Experimental Methods to Determine Coefficient of Friction
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How to Conduct an Experiment to Find Coefficient of Friction
To experimentally determine the coefficient of friction, we can follow a simple procedure. First, we need a surface on which the object can slide. We measure the force required to move the object and calculate the normal force. By dividing the measured force by the normal force, we can find the coefficient of friction.
Interpreting the Results of the Experiment
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Once the experiment is conducted and the coefficient of friction is calculated, we need to interpret the results. A coefficient of friction less than 1 indicates that the surfaces are relatively smooth, while a value greater than 1 suggests a rougher surface. Understanding the results helps us make informed decisions about materials, surfaces, and their interactions.
By understanding how to find the coefficient of friction and applying the appropriate formulas and methods, we gain valuable insights into the behavior of objects in contact. Whether it’s analyzing the motion of objects on inclined planes, circular paths, or conducting experiments, determining the coefficient of friction allows us to make accurate predictions and design efficient systems that minimize frictional losses.
Numerical Problems on how to find coefficient of friction
Problem 1:
A block of mass 5 kg is placed on a horizontal surface. The block is pulled horizontally with a force of 20 N. The block starts moving with an acceleration of 2 m/s^2. Determine the coefficient of friction between the block and the surface.
Solution:
Given:
– Mass of the block, m = 5 kg
– Applied force, F = 20 N
– Acceleration of the block, a = 2 m/s^2
To find the coefficient of friction, we can use the equation:
where is the force of friction.
Since the block is just starting to move, the force of friction can be expressed as:
where is the coefficient of static friction and N is the normal force. The normal force can be calculated as:
where g is the acceleration due to gravity.
Substituting the values into the equation:
Simplifying the equation:
Rearranging the equation:
Therefore, the coefficient of static friction is .
Problem 2:
A box of mass 8 kg is placed on a rough inclined plane. The angle of inclination is 30 degrees. The box starts moving down the plane when a force of 50 N is applied parallel to the plane. Determine the coefficient of kinetic friction between the box and the plane.
Solution:
Given:
– Mass of the box, m = 8 kg
– Applied force, F = 50 N
– Angle of inclination, θ = 30 degrees
To find the coefficient of kinetic friction, we can use the equation:
where is the force of friction.
The force of friction can be expressed as:
where is the coefficient of kinetic friction.
The normal force can be calculated as:
where g is the acceleration due to gravity.
The acceleration of the box down the plane can be calculated as:
Substituting the values into the equation:
Simplifying the equation:
Rearranging the equation:
Therefore, the coefficient of kinetic friction is .
Problem 3:
A car of mass 1200 kg is moving on a horizontal surface with a velocity of 20 m/s. The car comes to rest after a distance of 100 m. Determine the coefficient of friction between the car tires and the road.
Solution:
Given:
– Mass of the car, m = 1200 kg
– Initial velocity, u = 20 m/s
– Distance, s = 100 m
To find the coefficient of friction, we can use the equation:
where v is the final velocity, a is the acceleration, and s is the distance.
Since the car comes to rest, the final velocity is 0.
Substituting the values into the equation:
Simplifying the equation:
Rearranging the equation:
The acceleration can be related to the force of friction using the equation:
The force of friction can be expressed as:
where is the coefficient of friction and N is the normal force.
This article discusses about adiabatic turbine. The term adiabatic is often used in the field of thermodynamics. It refers to a system or boundary which does not allow heat transfer to take place.
A turbine is an essential device used in power plants which assists in generation of electricity. It contains elements that rotate. This rotation is transferred to generator which generates the electricity. We will study more about adiabatic turbines in this article.
What is an adiabatic system?
The system from which transfer of heat is restricted is called as adiabatic system. That is the heat cannot be transferred to surroundings and the heat cannot enter the system from surroundings.
The net heat transfer is zero. This is because of the walls of the system are adiabatic. Heat is not allowed to be transferred from the system. The entire content of heat remains inside the system only which becomes the internal energy of the system.
What is a turbine?
A mechanical device that is used to convert hydraulic energy to mechanical energy is called as turbine. The hydraulic energy comes in the form of moving water/steam which hits the propellers of turbine.
The movement of fluid that is the kinetic energy of fluid is transferred to the propellers of turbine. Because of this reason the shaft of turbine start rotating. This way the conversion of energy takes place from hydraulic to mechanical. Further sections will tell us more about turbine in detail.
Working of turbine
After discussing in the above section we now know that the turbine converts kinetic energy of fluid to mechanical energy.
In power plants, steam is used as the working fluid and in dams water is used as the working fluid. Working fluid here refers to the fluid which is responsible for rotation of shaft. The shaft rotates after working fluid strikes the surface of propeller. The rotating shaft is connected to generator which generates electricity.
What is adiabatic turbine?
Now we know the meanings of both adiabatic system and turbine. Let us see what is an adiabatic turbine.
An adiabatic turbine is a turbine whose walls are adiabatic. These walls don’t allow heat transfer through them. This way no amount of heat can escape the turbine. Hence, the net transfer from the turbine is zero. No heat is added to the turbine and no heat escapes the turbine when the turbine is adiabatic.
Similarly, the working of an adiabatic turbine is also same as that of normal turbine. In almost all cases, the walls of the turbine are kept adiabatic. Hence the working of an adiabatic turbine is same as that of a normal turbine that we have discussed in above sections.
Adiabatic gas turbine
As we have studied about the turbines used dams, they use water as the working fluid that rotates the propeller shaft in turbines.
When the working fluid used is a gas then the turbine is called as gas turbine. Gas turbines are mostly used in aeroplane power plants and thermal power plants used for generating electricity. The materials used in both the turbines are different because the type of working fluid used is different.
Adiabatic steam turbine
Adiabatic steam turbine is a turbine in which steam is used as the working fluid. Steam as we all know is the gaseous form of water.
The steam contains high kinetic energy which is transferred to the propeller of turbine. The turbine rotor starts moving when the high energy steam strikes the surface of propeller. Pressure drop will take place inside the turbine, while entering the steam is at high pressure. This pressure drops and the steam becomes low pressure steam after passing through turbine.
Adiabatic reversible turbine
The term reversible refers to a turbine in which all the processes are ideal. The losses de to friction or energy leaks are not present in reversible processes.
When we talk about adiabatic reversible turbine, it means the expansion process taking place inside the turbine is nearly ideal. Usually a multiple staged turbine is considered as a reversible turbine. When the walls are adiabatic, this turbine becomes adiabatic reversible turbine.
Adiabatic turbine equation
The equation used in adiabatic turbine is given below-
Work done by turbine is given by-
Wt= h2-h1
Where,
h2 is the enthalpy at point 2
h1 is the enthalpy at point 1
Adiabatic turbine efficiency
The efficiency is defined as the output gained from a system or device after pumping in some input.
We have already discussed in above section that a turbine is considered reversible when the expansion process in the turbine is ideal.
In reality, no device can be considered ideal, but a turbine can be made nearly ideal by increasing the number of stages of expansion process. This type of turbine is called as a multi staged turbine. The process of using multiple turbines is called as reheating.
Is a steam turbine adiabatic?
When the transfer of heat is restricted completely, a steam turbine can be said to be adiabatic.
The steam changes its phase to liquid after passing through the condenser. In a turbine only the pressure drop in steam takes place. The steam coming in with high pressure gets converted to a low energy steam at exit.
Turbines are adiabatic as the entire energy is taken to drive the turbine shaft.
No energy is lost in the form of heat or no energy enters the turbine in the form of heat. The only energy that participates in the energy transfer process is the kinetic energy of the fluid and kinetic energy of the turbine rotor.
Adiabatic turbine entropy
Before discussing about adiabatic turbine’s entropy, we shall know the meaning of entropy. Entropy’s widely accepted definition says that it is a measure of randomness in the system.
In actual turbines the entropy value increases. Whereas for reversible adiabatic processes the value of entropy generated is zero. This is because entropy is a state function and for a reversible process the end points are same and as the process is adiabatic, due to no heat transfer the change in entropy is zero.
is the frictional force and 
is the normal force.
moving with an acceleration 
. The frictional force acting on this object can be calculated using the formula:
. If we measure this force and calculate the normal force acting on the object, we can find the coefficient of friction using the formula mentioned earlier.
with a constant velocity 
. By using the equation of motion:
is the time taken to travel the distance, we can find the time. Next, we find the acceleration using the formula:
with a velocity 
is the angle of inclination.
is the force of friction.
is the coefficient of static friction and N is the normal force. The normal force can be calculated as:
is the coefficient of kinetic friction.
is the coefficient of friction and N is the normal force.
