Author Question: You throw a baseball straight up. Compare the sign of the work done by the gravitational force ... (Read 73 times)

LCritchfi · **on:** Jul 29, 2018

You throw a baseball straight up. Compare the sign of the work done by the gravitational force exerted by Earth on the object while the ball goes up with the sign of the work done by the same force while it goes down.

A) The work is positive on the way up and positive on the way down.
B) The work is positive on the way up and negative on the way down.
C) The work is negative on the way up and positive on the way down.
D) The work is negative on the way up and on the way down because gravity is always downward.

Question 2

A shopping cart moves with a kinetic energy of 40 J. If it moves at twice the speed, its kinetic energy is

A) 40 J.
B) 80 J.
C) 160 J.
D) not enough information