# 17 Constant Velocity Example: Detailed Explanation And Facts

In this article, we will discuss various examples of constant velocity with detailed explanations, and facts.

The following is a list of constant velocity examples:-

# Object in a circular motion

An object moving in a circular path of radius ‘r’ elapses a distance of 2πr on each round with angular velocity ω.

Consider an object in a circular motion that covers a distance ‘s’ in a certain time interval ‘t’. Let ‘θ’ be an angle made by the particle displacing from its initial position.

The linear velocity of the particle is a change in the position of the object in time t.

v=s / t

‘s’ is a displacement of a particle which is an arc length and can be calculated as a product of angle made by the particle on displacement and the radius of the circle.

s= θr

On substituting this in the above equation, we have

v=rθ/ t

Since the angular velocity is equal to the change in angle with respect to time; we can rewrite the equation as

v=rω

Where ω is an angular velocity

The angular velocity of the object is constant if the linear velocity of the object remains constant.

# Motion of an object due to Centripetal Force

The object in a centripetal motion exerts the centripetal force which is acting towards the center of the circular path and the linear velocity of the object remains perpendicular to the centripetal force.

The centripetal force exerted on the object in a circular motion is given by the equation

F=mv2/r

Where r is the radius of the circular path

V is a linear velocity

M is a mass of the particle

If there is an external force acting on the object that keeps the object in the circular motion the

ma=mv2/r

a=v2/r

v2=ar

Hence, the velocity of the object is constant if the angular acceleration of the object is constant.

# Revolution of a moon around the Earth

The velocity of a moon revolving around the Earth is almost at a constant rate. The moon completes one revolution around the Earth in 27.3 days which is equal to T=27.3 x 24 x 60 x 60=23,58,720 seconds

The distance of the moon from the center of the Earth is 3,84,000 km

The distance covered by the moon in one revolution is equal to the circumference of the circular path. Hence, the velocity of the motion is V= 2π r/T

V= 2π x 384000 x 1000/2358720=1022 m/s

The velocity of a moon orbiting around the Earth is 1022m/s and is constant.

# A person walking on the street at a constant speed

A man walking on the street at his constant speed will cover an equal distance in an equal interval of time. This can be an example of a constant velocity.

# Drawing water from a well with the help of a pulley

While drawing water from a well using a pulley, the force is applied downward but the reaction force is in the upward direction. The velocity of the bucket lifting up depends upon the length of the rope stretched on every pull.

The length of the rope that is stretched depends upon the movement of the arm and the length of the hand. Hence the velocity of the bucket and the angular acceleration of the pulley will be constant.

# A ray of light

A light travels in a straight line at a constant speed of 3 x 108 m/s. A light shows various other phenomena in nature like scattering, dispersion, reflection, refraction, total internal refraction, interference, diffraction, etc.

The speed of light is equal to the product of the wavelength of the light and the frequency of the electromagnetic wave as c=fλ.

# Speed of the object in a vacuum

If the object falls in the vacuum, it accelerates at a constant speed and experiences a free fall. All the objects in the vacuum will move at the same speed irrespective of their shape, size, density, or weight. The velocity of the object in a motion in a vacuum is constant.

# Sound wave

The sound wave travels at a speed of 332m/s at normal temperature and pressure conditions. The speed of sound is determined by the distance traveled by the sound waves in a certain time duration.

The velocity of a sound wave varies depending upon the density of different mediums and sound waves travel at a constant rate.

# Clock

The minute hand, an hour hand, and a second hand on the clock move at a constant speed. The point at the center where all the hands are attached resembles an instantaneous central point.

A clock measures angle of 360 degrees and each minute on the clock is equal to 1 degree. A second-hand travels 360 degrees in one minute, hence the speed of the second hand is

A minute hand covers 360 degrees in 1 hour, hence the velocity of the minute hand is

An hour hand displaces 30 degrees in 1 hour, therefore the velocity of an hour hand is

# A car traveling on a road at constant speed

A car moving at a constant speed will elapse equal distance in an equal duration of time hence is an example of constant velocity. The velocity of a car is measured as the ratio distance covered by the car from its initial position to reach a certain distance in time ‘t’.

# A ball moving on a plane surface

A ball can travel at the same speed unless exerts an external force that makes increases or decreases the speed of the ball to displace its position.

# Fan

A fan rotating at a constant speed gives a constant angular velocity until the speed of the fan is changed.

# Hourglass

A sand-filled hourglass is dropped down from the hole at a constant velocity.

The hourglass is designed such that the frictional forces due to sand and glass are canceled and the constant pressure is exerted on the hole that makes the sand drop down from the hole. The sand filled in glass drops at a constant rate and is hence used as a timer.

# Train

A train is an example of a constant velocity, which elapses the same distance in a certain interval of time.

# Electric vehicles without gears

Electric vehicles work on electric energy. A vehicle without gear will move at the same speed and in the front direction only.

# Photon

A photon being a light particle is easily carried away and moves with the speed of light. The velocity of a photon is constant.

# Birds Flying

The velocity of the birds is mostly constant while they are flying. Most of the birds are observed to sway at constant velocity. Therefore, we can estimate the expected date and time of birds venturing from the far locations.

## What is constant velocity?

The velocity of the object is defined as the rate of change of position of an object in a fixed interval of time.

If the distance elapsed by the object in a given time interval will be constant for every time interval then the velocity of the object will be constant.

Hence,

x2-x1=Constant

For the velocity to be constant, the change in the position of the object has to be constant along with time.

## Position-Time Graph for constant velocity

The displacement of the object in time is represented in the following position-time graph.

The slope of the position-time graph gives the velocity of the object between the two time intervals while displacing from one position to another. The slope of the graph is linear and is constant throughout the slope.

Read more on How To Calculate Negative Velocity: Example And Problems.

## Q1. If an object is traveling at a constant velocity of 12m/s, then calculate the distance covered by the object after 1 minute.

Solution: 1 minute=60 seconds

The distance covered by the object in 60 seconds traveling at a speed of 12m/s will be

= 12m/s\times 60s=720m

Hence, the distance traveled by the object in 1 minute is 720m.

## How does a graph of velocity v/s time will looks like for a constant velocity?

An object with constant velocity will travel in a straight line covering an equal distance in a given time interval.

Since the velocity of the object will be constant all the time, the acceleration of the object which is a slope of the graph will be zero. This implies that the slope of the graph will be a straight line.

AKSHITA MAPARI

Hi, I’m Akshita Mapari. I have done M.Sc. in Physics. I have worked on projects like Numerical modeling of winds and waves during cyclone, Physics of toys and mechanized thrill machines in amusement park based on Classical Mechanics. I have pursued a course on Arduino and have accomplished some mini projects on Arduino UNO. I always like to explore new zones in the field of science. I personally believe that learning is more enthusiastic when learnt with creativity. Apart from this, I like to read, travel, strumming on guitar, identifying rocks and strata, photography and playing chess. Connect me on LinkedIn - linkedin.com/in/akshita-mapari-b38a68122