Question

A 12.70 g bullet has a muzzle velocity (at the moment it leaves the end of a firearm) of 430 m/s when rifle with a weight of 25.0 N. Calculate the recoil speed (in m/s) of the rifle.

Answer 1

Answer:

V = 2.14 m/s

Explanation:

Given,

The mass of the bullet, m = 12.7 g

                                              = 0.0127 Kg

The velocity of the bullet, v = 430 m/s

The weight of the rifle, w = 25 N

∴ The mass of the rifle, M = 25/9.8

                                           = 2.55 Kg

According to the law of conservation of momentum,

                                        MV + mv = 0

Therefore, the recoil velocity of the gun

                                           V = -mv/M

Substituting the given values in the above equation

                                            V = -0.0127 x 430 /2.55

                                                = -2.14 m/s

The negative sign indicates the direction of V with respect to v.

Hence, the recoil velocity of the gun is, V = 2.14 m/s