A rifle fires a bullet of 60 g with a velocity of 50 m/s. The velocity of recoil of rifle is 2 m/s. The mass of rifle is

Options

A. `3.0 kg`
B. `2.0 kg`
C. `1.5 kg`
D. `1.0 kg`

Answer

C

Explanation

Mass of bullet = 60 g
Velocity of bullet = 50 m/s
Velocity of recoll of rifles = 2 m/s
Mass of rifle = ? = M
Using law os conservation of momentum.
`M xx` velocity of recoil of rifle
= Mass of bullet `xx` Velocity of bullet
`implies M xx 2 = 60 xx 50`
`implies M = ( 60 xx 50)/(2 ) = 9(300)/(2) = 1500 g = 15 kg`