A bullet of mass 3.3 10-3 kg moving at 750 m/s impacts with a large fixed block of wood and travels 5 cm before coming to rest. Assuming that the deceleration of the bullet is constant, find the force exerted by the wood on the bullet?

Question

A bullet of mass 3.3  10-3 kg moving at 750 m/s impacts with a large fixed block of wood and travels 5 cm before coming to rest. Assuming that the deceleration of the bullet is constant, find the force exerted by the wood on the bullet?

I am confused on how to do this last problem, its my Last problem to do for my homework and its one that determines if I get an a on the homework or a b. PLEASE HELP THANKS

drwls · Answer

Calculate the kinetic energy of the bullet before impact. You know the formula for that.

The force exerted on the block times the distance the block moves is work done by the bullet on the block, and equals the initial kinetic energy.