College Physics

Question

A 7.50g-bullet has a speed of 555 m/s as it leaves the muzzle of a rifle. If the barrel of the rifle is 0.950 m, what is the average force exerted on the bullet by the ammunition?

Answer 1

Hi Johari

The assumption here is that the force acts on the bullet throughout the barrel, then is in free flight. With that as the case, we can use the equation below:

Vf^2 = Vi^2 + 2*a*x to find the average acceleration through the barrel. Since Vi = 0 , a = 555^2 /(2*.950)

Average acceleration = 162,118 m/sec^2

Then, average force = mass of the bullet * avg. acceleration = 0.0075*162,118 = 1216N