A hunter has a machine gun that can fire 50g bullets with a velocity of `900 ms^(-1)`. A 40 kg tiger springs at him with a velocity of `10 ms^(-1)`. How many bullets must the hunter fire into the tiger in order to stop him in his track?

Explanation

Mass of bullet, m = 50g = 0.05kg , Velocity of bullet, v = 900 `ms^(-1)`
Mass of tiger, M = 40 kg , Velocity of tiger, V = `10 ms^(-1)`
Let n be number of bullets reqired to be pumped into the tiger to stop him in his track.
If the bullets and the tiger are supposed to constitute one isolated system, then the magnitude of the momentum of n bullets should be equal to the magnitude of momentum of the tiger.
`:. n xx mv = MV ( or) n=(MV)/(mv) :. n=(40 xx 10)/(0.05 xx 900) = 8.89 ~~9`