Author Question: A 0.140-kg baseball is thrown with a velocity of 27.1 m/s It is struck by the bat with an average ... (Read 39 times)

cmoore54 · **on:** Jul 29, 2018

A 0.140-kg baseball is thrown with a velocity of 27.1 m/s It is struck by the bat with an average force of 5000 N, which results in a velocity of 37.0 m/s in the opposite direction from the original velocity.

How long were the bat and ball in contact?
A) 4.30 10-3 s B) 3.07 10-2 s C) 1.79 10-3 s D) 1.28 10-2 s

Question 2

A popular swinging-balls apparatus (Newton's cradle) consists of a series of identical elastic balls suspended by strings so they barely touch each other.

When two balls are pulled away from one end and released, they strike the row of balls and two balls pop out from the other end. If instead, one ball popped out with twice the speed, this would violate the conservation of
A) momentum.
B) energy.
C) both of these
D) none of the above