Question

A bullet of mass 4.0g is fired from a rifle of mass 2.0kg with muzzle velocity of 380m/s. What is the initial recoil velocity of the rifle?

Answer 1

Answer:

v = 0.76 [m/s]

Explanation:

The linear momentum generated by the shot must be calculated. This can be calculated using the following expression.

$P=m*v$

where:

P = linear momentum [kg*m/s]

m = mass [kg]

v = velocity [m/s]

$P=0.004*380\\P=1.52[kg*m/s]$

Now we can calculate the recoil velocity, because the momentum is equal for the rifle.

$P=m*v\\v = P/m\\v = 1.52/2\\v = 0.76[m/s]$