Question

a uniform force of 4N acts on a body of mass 8 kg for a distance of 2 metres the K.E acquired by the body is

Answer 1

Given:

• Force acting on body = 4N.
• Mass of body = 8 kg.
• Distance for which force acted = 2 metres.

To find:

Kinetic energy acquired by body ?

Calculation:

In these type of questions, it is best to apply WORK-ENERGY THEOREM :

• This theorem states : The net work done by all force is equal to change in kinetic energy of the object.

Let's assume that the body started from rest , so initial KE is zero.

Then, we can say :

$W = \Delta KE$

$\implies \: F \times d = KE_{f} - KE_{i}$

$\implies \: 4 \times 2 = KE_{f} - 0$

$\implies \: KE_{f} = 8 \: joule$

So, KE acquired by object is 8 Joule.