Question

23. The motion of a body of mass 5 kg is shown in the velocity-time graph.

Find from the graph
1. The acceleration.
ii. The force acting on the body.
ii. The change in momentum of the body in 2 s after the start.​

Answer 1

Answer: Acceleration 2.5 from v=u intially at rest then u=0

Froce 12.s f=ma

Momentum = mv = 5*5=25

Answer 2

Given:

The mass of the body m= 5 kg

To find:

The acceleration, force acting on the body, and change in momentum.

Solution

As m= 5

According to graph

initial velocity u=0

final velocity v=20 m/sec

According to the equation of motion

v=u+at

20=0+a(8)

20=a(8)

a=2.5 m/sec²

Now the force acting on the body.

F=m.a

F=5×2.5

F=12.5 N

Now the change in momentum

p=m×v

=5×5

=25 kgm/sec

so the answers are

The accelaration=2.5 m/sec²

The force acting on the body F=12.5 N

The change in momentum p=25 Kg.m/sec