A gun of mass 3 kg fires a bullet of mass 30 g. The bullet takes 0.003 s to move through the barrel of the gun and acquires a velocity of 100 m/s Calculate:

(i) The velocity with which the gun recoils.


(ii) The force exerted on gunman due to recoil of the gun

(i) For gun,

m - 1=3 kg


v1=?


For bullet,


m2 = 30 g = 0.03kg


v2 = 110m/s


By law of conservation of momentum


M1×v1 = m2×v2


3 × v1 = 0.03 × 110


V1 = 0.03 × 110/3


V1 = 1.1m/s


Hence, the velocity of recoil of gun is 1.1m/s


(ii) Acceleration of bullet, a = v-u/t


110-0/0.03 = 3666.6m/s2


Force, F = ma


= 0.03 × 3666.6


= 109.9N


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