Police are testing a new riot control gun. It shoots bullets of mass 150g at a s
ID: 1513214 • Letter: P
Question
Police are testing a new riot control gun. It shoots bullets of mass 150g at a speed of 200 m/s They test it by trying to knock over at a 50 kg log balanced on end. They can choose between bullets made of rubber which bounce back, bullets made like little sand bags which just drop when they hit, or bullets made of bluetack which stick on to the target. Which will be most effective at knocking things over and WHY. Do some momentum calculations that show this. The biggest change in momentum will be the most effective..Explanation / Answer
Momentum of bullet = mV = 0.150*200 = 30 N.s
a) Bounce back , finalmomentum = -30
momentum imparted= 30-(-30) = 60 N.s
b) drop after hit
final momentum = 0
change in momentum = 30 N.s
c) get stuck , final momentum 0
chnage in momentum = 30 N.s
option first is the answer