An object, initially at rest, is given a constant force such that it acquires a uniform acceleration of 0.20 m/s2. The mass of the object is 15 kg.


If the frictional force is neglected, then what is the work done by the force after five seconds?

We have,

Mass, m = 15 kg

Acceleration, a = 0.20 m/s²

Initial velocity, u = 0

Final velocity = v

Time, t = 5 s

Now,

v = u + at

=> v = 0 + (0.2)(5)

=> v = 1 m/s

Since, there is no lose of energy due to any frictional force. Work done on the body is equal to the gain in KE.

So, W = ½ mv² – ½ mu² = ½ (15)(1²) = 7.5 J