Question

a bullet of mass 10 g is fired at a speed of 400 m/s from a gun of mass 4 kg.what is the recoil velocity of the gun 

Answer 1

here no external force is acted (neglect air resistant) hence momentum of system(gun+bullet) is conserved 
initial momentum = finial momentum
let the recoil velocity of gun = v
0.01*0 + 4*0 = 0.01*400 + 4*v
v = -1m/s
hence gun recoil with velocity 1m/s 

Answer 2

Explanation:

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