A rifle with a barrel length of 60 cm fires a 10 g bullet with a horizontal speed of 400 m/s. The bullet strikes a block of wood and penetrates to a depth of 12 cm.

a. What resistive force (assumed to be constant) does the wood exert on the bullet?

b. How long does it take the bullet to come to rest?

c. Draw a velocity-versus-time graph for the bullet in the wood.