Question

A body of mass 4 kg at rest is acted upon a Force = 20 N for 3 s. What will be the velocity of the body after the force stops acting.?

• A. 15
• B. 16
• C. 17
• D. 18

Answer 1

The correct option is A 15

Impulse on the body would be $J-F\Delta t$, where $F=20N$,$t=3s$ also impulse is change in momentum :$J=M\Delta V$

so,

$m(v-u)=Ft,m-4kg,u=0m/s$ gives,

$4V=20\times 3\to V=15m/s$