Question

Hey guys!! An object of mass, m is moving with a constant velocity ,v. How much work should be done on the object in order to bring the object to rest?​

Answer 1

Answer:

Mass of Object = m

Velocity of object = v

Work done = Force * Displacement

Force = m * a

So work done = m * a * v

Third equation of motion,

v² = u² + 2as

s = v² - u² / 2a

Now, Work done = m * a * ( v² - u² / 2a )

= m * ( v² - u² / 2 )

= mv² / 2 - mu² / 2

So mv² / 2 - mu² / 2 work should be done to make object at rest.

Hope it help..

Answer 2

Answer:

Since the object is in motion so ,

Kinetic Energy = ½mv²

The kinetic energy of the object when it comes to rest = 0

Work done on the object= Change in kinetic energy

= ½mv²-0 = ½mv²