Question

1. Starting from rest, a 5 kg block is acted upon by
only one force as indicated in the figure. Find the
work done by the force in first four seconds.
​

Answer 1

Explanation:

Change in velocity=

mass

area under F-t graph

=

5

40+(−10)

=6m/s

Work done by the force = change in kinetic energy

W=ΔK.E.=

2

1

(10)6

2

=180J