Question

A bullet of mass 20o gm is fired from a gun , with a velocity of 30m/s . If the mass of gun is 10kg .Find the recoil of gun

Answer 1

Given-

m1 - mass of bullet = 200 gm = 0.2 kg

m2 - mass of gun = 10 kg

V1 - velocity of bullet = 30 m/s

V2 - velocity of gun = ??

Solution-

According to law of conservation of linear momentum,

Linear momentum=Linear momentum

before firing after firing

0 = m1 V1 + m2 V2

V2 = -m1 V1/m2

= -0.2×30÷10

V2 = - 0.6 m/s

i.e., Recoil velocity of gun = -0.6 m/s

The negative sign shows that the gun moves opposite to the direction of motion of the bullet.