Question

From a rifle of mass 5kg, a bullet of mass 100g is fired with an initial velocity of 25m/sec. Calculate the initial recoil velocity of the rifle.​

Answer 1

Answer:

v1= -0.5m/s negative sign indicates opposite direction to the direction of bullet

Explanation:

100g=0.1kg

momentum before fire=(m1+m2)*v

since v=0 then momentum=0

momentum after fire=m1v1+m2v2

=5v1+0.1*25

=5v1+2.5

momentum before fire=momentum after fire

0=5v1+2.5

5v1=-2.5

v1= -0.5 m/sec