Author Question: A ball is tossed vertically upward. When it reaches its highest point (before falling back downward) ... (Read 78 times)

fasfsadfdsfa · **on:** Jul 29, 2018

A ball is tossed vertically upward. When it reaches its highest point (before falling back downward)

A) the velocity, acceleration, and the force of gravity on the ball all reverse direction.
B) the velocity and acceleration reverse direction, but the force of gravity on the ball remains downward.
C) the velocity is zero, the acceleration is zero, and the force of gravity acting on the ball is directed downward.
D) the velocity is zero, the acceleration is directed downward, and the force of gravity acting on the ball is directed downward.
E) the velocity is zero, the acceleration is zero, and the force of gravity acting on the ball is zero.

Question 2

Equal but opposite charges Q are placed on the square plates of an air-filled parallel-plate capacitor. The plates are then pulled apart to twice their original separation, which is small compared to the dimensions of the plates.

Which of the following statements about this capacitor are true? (There may be more than one correct choice.)
A) The capacitance has doubled.
B) The electric field between the plates has increased.
C) The energy stored in the capacitor has doubled.
D) The energy density in the capacitor has increased.
E) The potential difference across the plates has doubled.