Question

A bullet of mass 20 gm is fired from a rifle of mass 8 kg with a velocity of 100 m/s. The velocity of recoil of the rifle is

Answer 1

gun mass: 8kg(m1)

bullet mass: 20g(m2)

velocity of the bullet:100m/s(v2)

recall velocity of the Piston aur rifle:?(v1)

now you have to solve this by putting the method

m1v1+m2v2=m1u1+m2u2

now here question arises what do you mean by u1 and U2 it means that you is for the velocity before the the firing and v for the velocity after the firing

as the velocity before firing was zero because there is no moment in gun and there was no movement in bullet so you is equal to zero so m1u1+m2u2*=0

I think now you can solve this problem