A rifle man, who together with his rifle has a mass of `100 kg,` stands on a smooth surface and fires `10` shots horizontally. Each bullet. has a mass `10 g` and a muzzle velocity of `800 m//s`,
a. What velocity does the rifle man acquire at the end of `10` shots?
b. If the shots are fired in `10 s`, what will he the average force exerted on him?
c. Compare his kinetic energy with that of `10` bullets

Options

A. `8ms^(-1)`
B. `0.8ms^(-1)`
C. `0.08ms^(-1)`
D. `-0.8ms^(-1)`

Answer

B

Explanation

According to law of conservation of momentum,
`100v=-(10)/(1000)xx10xx800 ie, v=0.8 ms^(-1)`