Question

A body of mass 500 gr. moving with 10 m/s increases to 20 m/s when acted upon a force. The change in KE is _____ *

Answer 1

Answer:

Hence, change in KE = 250 J

Explanation:

Given,

Mass of body = 50 gr (m)

Final velocity of the body = 20 m/s (vf)

Initial velocity of the body = 10 m/s (vi)

We know that,

Change in Kinetic Energy = 1/2mvf - 1/2mvi

Change in KE = 1/2(50 × 20) - 1/2(50 × 10)

Change in KE = 1/2 × 1000 - 1/2 × 500

Change in KE = 500 - 250 = 250

Hence, change in KE = 250 J