Question

A force of 10N acts on a body of mass 2kg. If the body was initially at rest, calculate the velocity gained by it in 5 seconds. ​

Answer 1

Explanation:

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

Step 1: Acceleration of the body

F=ma

⇒a=mF=2 Kg10 N=5m/s2

 

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

Answer 2

refer to the attachment