Conservation Of Momentum Examples:Detailed Insight

Conservation of momentum examples is a universal factor and application of the quantity called momentum. Momentum is a collection of vector quantities, namely force, mass, and velocity.

Below are some examples that give us a better understanding of the conservation of momentum.

Particle Collision

As we all know, several factors are responsible for any action in physics. Each time we dive into the attributes of contributing to the actions, we go deep into how momentum is conserved in each case.

What do we mean when we say that momentum is conserved? This simply means that there will be precisely no changes in physical form. In this case of particle collision, the momentum of the particle before they begin to collide will be the same even after they finish collision.

Momentum is simply the factor or a physical quantity that majorly defines the mass and velocity of a particular body. When a body is considered to be in motion, several different factors will be responsible for that same motion.

In the case of momentum, we know that it directly impacts mass, velocity, and force. Also, this will mainly have a significant dependency on the direction of the force acting on the body under motion.

So we need to know the kind of quantity that will keep the body intact. The object’s momentum will be the same before and after the body, which is under constant motion. Therefore it is the same for the case of particle collision.

Rocket Propulsion

Rockets are the one main fascination for every person interested in it. Those who are keenly watching rockets or being in touch with its study know that the momentum starts precisely when the rocket is propelled.

There is no momentum until and unless it is allowed to propel, but once it is done, the momentum starts instantly. Therefore the conservation of momentum occurs at the early stage of propulsion, and when they are ready to launch, the momentum is zero.

There will be momentum in the downward direction of the rocket. When the fuel is ready and fired for launching, the gases expelled by the rocket travel downward. This is actually equal to the momentum acting in the upwards direction.

In detail, let us see how the conservation happens. There will be momentum present in the rocket at the base level, and that is in a downward direction. The momentum is in action before the launch. Hence the force acting downwards will contribute to the momentum.

Now when the launch is started, the rocket will leave gases so that it will travel in a downward direction. So when the rocket moves upwards, there will be momentum happening. And then, this momentum will nullify the downward momentum.

Therefore when both the opposite momentum cancels out on each other, the momentum is conserved and becomes zero.

Helicopter Rotor

One of the standard conservation of momentum examples is the rotor in general. But here, we deal with the helicopter rotor. Angular momentum is in action with the rotor of the helicopter.

When the helicopter rotates, the rotor present at the end of it will provide a counter thrust on the body to keep the helicopter in proper balance. This will keep the helicopter in proper motion as well without any shaking.

Here the angular momentum is conserved despite the action of external forces on it. Because the helicopter is mainly in action in the air, the balance is one of the most crucial factors.

Balancing forces is also a significant thing to be kept in mind while we detail momentum factors. Momentum is conserved when the rotor moves clockwise and anticlockwise.

Angular momentum is conserved in this rotor when it keeps the helicopter in balance.

“Helicopter” by Bri-Lanie is licensed under CC BY-NC-SA 2.0

Ice Skaters

Generally, when ice skaters spin on the floor, they use very little friction. Since the area of the skating wheel is very small, the friction also will be less respectively.

Friction is the factor between the ground and the body under motion touching the ground. The torque acting the skater is negligible since the friction present is minimal.

Now the skater can increase the speed by pulling the arms and legs to increase the spin. The reason behind it is that the moment is gained to contribute to the rise in spin rate.

In this case, the angular momentum is analogous to the linear momentum, which is conserved at any moment. So ice skating is one of the common conservation of momentum examples.

We know that the angular momentum formula is L = mvr, where m is the mass, v is the velocity, and r is the radius. We include radius because it will be in circular motion always.

Hence we neglect the torque present in the skating on ice due to the significantly less friction contributed to the motion. In this way, conservation of momentum is possible.

conservation of momentum examples
“Ice Skaters” by jgrimm is licensed under CC BY-NC-ND 2.0

Ballistic Pendulum

The ballistic pendulum is the one that measures the momentum of a bullet. Not only bullets but also the spin of a golf ball when in motion. The momentum in a bullet is conserved when it hits a stationary pendulum.

The ballistic pendulum measures the momentum of an object that will undergo any angular motion having angular momentum. This will also prove the conservation of momentum.

When the bullet hits the stationary pendulum, it will start oscillating with the new velocity gained. And there is no conservation of energy concept here because it will dissipate internally in terms of heat and the energy reason for the deformation.

Therefore in this way, the momentum is conserved due to the non-conservation of the energy. However, the energy cannot be conserved as it will dissipate internally. Also, the momentum is conserved at any cost since the force is also dealt with in this case.

Gun Recoil

Gun recoil is one of the most important factors that help us discover several factors that abide by it. We may learn as much physics using the gun recoil.

When the bullet is fired out of a gun, it will first go backward and move forward before coming out of the system. Because when the shunt moves backward which has the bullet will experience the backward momentum.

When the bullet is fired, it will first experience a backward momentum and the forward momentum. This is due to the back and forth motion of the bullet that is placed. The trigger will now help move the bullet to be fired.

In both ways, there is momentum working out, and by the way, it will both nullify each other. Backward and forward momentum will cancel out each other, conserving the momentum. Hence the momentum in the last stage will be zero.

During the firing of a bullet, it will experience a kick kind of motion, and the momentum before firing is zero, and when the bullet is forced, it will gain much force and is then moved out of the system.

Therefore the momentum is zero at the end of the firing. Recoiling is one of the most seen factors that will help find all kinds of physics present inside the process. Also, this conservation of momentum follows Newton’s Third Law.

Hydraulic Jump

Following the law of conservation of momentum, it is known that in any closed system considered; the momentum is conserved by all means. There is momentum before and after any kind of physical process which invokes force, mass, and velocity.

The momentum will be zero and is conserved. This means that a hydraulic jump that is in a rectangle will conserve momentum. Although being a closed system, it will lose energy.

The conservation of momentum also helps in fluid mechanics who will calculate the thrust given to the system. This will save energy but will eventually lose momentum in the end.

Hydraulic jumps are the basic concept of open-channel flow. There is momentum before and after the jump when momentum is considered in umps.

The formula regarding conservation o momentum and mass will give us a better result for the internal yield of the system.

Break System In Vehicles

Usually, when traveling by car or any other vehicle, when the breaks are applied, we move forward and then backward. There are Newton’s Laws that will be applied here and come into action.

The momentum before the break is present and is zero, and then the momentum after breaks will be zero because the body will be in motion. Therefore the momentum will cancel out each other accordingly.

Generally, when breaks are applied to a vehicle, the kinetic energy will be converted into thermal energy. While the vehicle is in motion (kinetic energy), the breaks will be applied to bring the vehicle to a stop.

The breaks work in the motion opposite to that of the direction of the motion of the vehicle. The retarding force comes into play here. The momentum will be zero before applying break, and when the break is applied, the momentum gained will equal the previous one.

In this way, the momentum will be conserved and zero value. The applied force will have momentum, which will undoubtedly be changed due to the application break in a vehicle.

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