Question

An object having mass 2kg is moving with constant velocity of 5m/s . How much force is acted on the body

Answer 1

The graph is given between force and time.

Area under Force-time graph gives Impulse.

So, Total area in 20s is

A

2

=

2

1

×5×20

=50m

2

A

1

=20×5=100m

2

A

3

=

2

1

×10×(−20)=−100m

2

Therefore total area A=A

1

+A

2

+A

3

A= 50m

2

Work done W= F×s

=(F×t)×v

Initial velocity is given, v=$$5m/s$$

Work done, W=Ft.v

W= 50 x 5 J

= 250J