Question

A body of mass 2 kg is moved from rest by applying a force of 10N for 5 seconds. Find the displacement caused in the body in 5 seconds.

Answer 1

Answer:

Given: F=10 N,m=2 kg,t=3s, Initial velocity, u=0

Step 1: Acceleration of the body

F=ma

⇒a=  

m

F

​

=  

2 Kg

10 N

​

=5m/s  

2

 

 

Step 2: Velocity acquired by the body after 3s

As acceleration is constant, therefore applying equation of motion:

v=u+at=0+5×3=15m/s

Step 3: Change in momentum

Change in momentum = Final momentum − Initial momentum  

                                      =mv−mu=m(v−u)

                                      =2kg (15 m/s−0)

                                      =30 kg-m/s

Explanation: Hope It helps you