A 200-g mass attached to the end of a spring causes it to stretch 5.0 cm. If another 200-g mass is added to the spring, the potential energy of the spring will be
A) twice as much.
B) times as much.
C) the same.
D) 4 times as much.
E) 3 times as much.
Question 2
When a ball is thrown straight up, the acceleration at its highest point is
A) upward.
B) downward.
C) zero.
D) horizontal.
E) minimum.