Question
A gun of mass 10 kg fires 4 bullets per second. The mass of each bullet is 20 g and the velocity of the bullet when it leaves the gun is 300 m s-1. The force required to hold the gun when firing is
6 N
8 N
24 N
240 N
Solution
C.
24 N
Momentum of one bullet
p = mv
= 20 × 10-3 × 300
p = 6 kg m s-1
N = number of bullet per sec = 4
∴ = change of momentum per sec or force
= N ( p 0 )
= 4 × 6
= 24 N
