Question

from the rifle of mass 4 kg A bullet of mass 50 gram is fired with an initial velocity of 35m/s . calculate the initial velocity of refile.

Answer 1

Use m1u1+m2u2=m1v1+m2v2

Answer 2

heya it's Aastha....

Bullet Mass = 50 g
Rifle Mass = 4kg
Intial Velocity = 35m/s
Intial recoil velocity of the rifle = x

Here mass of bullet = 50 g
                             = 50/1000
                             = 0.05 kg

Now ...
              Momentum of Bullet = Momentum of gun
or           Mass of bullet × Velocity of bullet = Mass of gun × Recoil velocity of gun

             0.05 × 35 = 4 × x
            x = 0.05 × 35 ÷ 4
              = 1.75 ÷ 4
             = 0.4375 m/s