Question
A machine gun fires $20$ bullets per second into a target. Each bullet weighs $150 $ gms and has a speed of $800 \,m/sec$. Find the force necessary to hold the gun in position ............ $N$
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Answer
(d)$F = mnv = 150 \times {10^{ - 3}} \times 20 \times 800 = 2400\;N.$
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