When will a body of mass 20   kg moving at 15   m   s - 1 , subjected to a retarding force of…

When will a body of mass 20 kg moving at 15 m s-1, subjected to a retarding force of 100 N, come to rest?
  1. 3 s
  2. 6 s
  3. 1.5 s
  4. 9 s

Solution

Given that 

Retarding force F=100 N 

Initial velocity u=15 m s-1

Mass m=20 kg

From newton's second law 

F=ma

⇒a=Fm=10020=5 m s-2

From equation of motion 

v=u+at

⇒0=15-5t

⇒t=3 s

Asked in: AP EAMCET 2020 (23 Sep Shift 1)

Practice more Motion In One Dimension questions on Aicharya