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Question

A 4.0-g bullet leaves the muzzle of a rifle with a speed of 326 m/s. What force (assumed constant) is exerted on the bullet while it is traveling down the 0.79-m-long barrel of the rifle?

 N

Answer 1

F·s = mv²/2; F = mv²/(2s) = 4·10^-3kg·(326m/s)²/(2·0.79m) = 269.1 N