A 5.00 gram bullet has a velocity of 300 m/s.It strikes a block of wood and penetrates to a distance of 2.00 cm.The average force of the block of wood on the bullet is
A) 9,340 N.
B) 11,250 N.
C) 15,200 N.
D) 19,500 N.
E) 21,400 N.

Question

Quizplus · Accepted Answer

We can use the formula for average force:

F = m*(v_f - v_i)/t

In this case, we assume the time of impact t = 2d/v_f, where d is the distance the bullet penetrates.

F = (0.005 kg)*(0 - 300 m/s)/(2*(0.02 m)/(300 m/s))

F = 11,250 N

Therefore, the best choice is B, which is 11,250 N.

A 500 Gram Bullet Has a Velocity of 300 M/s