a hunter has a machine gun that can fire 50 g bullets with a velocity of 150 m/s . a 60 kg tiger springs at him with a velocity of 10 m/s . how many bullets must the hunter fire per second into the tiger in order to stop him in his track
Mass of a bullet, m = 50 g = 0.05 kg
Velocity of a bullet, v = 150 m/s
So, momentum of each bullet, p = mv = 7.5 Ns
Mass of the tiger, M = 60 kg
Velocity of the tiger, V = 10 m/s
Momentum of the tiger, P = MV = 600 Ns
To stop the tiger, let n bullet be fired such that momentum of the n bullets combined is equal to the momentum of the tiger.
np = P
=> n(7.5) = 600
=> n = 80
So, 80 bullets are to be fired to stop the tiger.