A 5.4 g bullet leaves the muzzle of a rifle with a speed of 334 m/s. What force (assumed constant) is exerted on the bullet while it is traveling down the 0.95 m long barrel of the rifle?

Question

A 5.4 g bullet leaves the muzzle of a rifle with a speed of 334 m/s. What force (assumed constant) is exerted on the bullet while it is traveling down the 0.95 m long barrel of the rifle? 
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