Question

A 10 - g bullet moving directly upward at 1000 m/s strikes andpasses
through the center of mass of a 5-kg block initially at rest. Thebullet
emerges from the block, moving directly upward at 400 m/s.

a) What is the speed of the box immediately after the collisionwith the
bullet?
b) To what maximum height does the block then rise above itsinitial
position?
c) How much energy is lost during the collision?

Answer 1

Apply conservation of linear momentum and solve for the speed achieved by the block after the collision 1 kg 0000 m/s)+(5 ke)10 8 008( (400 m/s)+(5 kg) 1000 g v1.2 m/s Apply conservation of energy and solve for the maximum height reached by the block. box box 1.2 m/s 2(9.8 m/s' 17.35% 10-2 ml 7.35 cm or The loss in the energy is equal to the change in the initial and final energies of the system of block and bullet. 2 1 10 21000k kg (1000 m/s) +-(5 kg) (0) 1004.400 kg (400 m/s)'+-(5 kg) (1.2 m/s ) ! 1000 -4.1964 x10 J