A juggler throws two balls up to the same height so that they pass each other halfway up when A is rising and B is descending. Ignore air resistance and buoyant forces. Which statement is true of the two balls at that point?
A)There is a residual upward force from the hand on each ball.
B)There is a greater residual force from the hand on A than there is on B.
C)Only gravity acts on B but there is an additional residual force from the hand on A.
D)There is an additional downwards force besides gravity on each ball.
E)The only force acting on each ball is the gravitational force.

Question

Quizplus · Accepted Answer

At the point where the balls pass each other halfway up, the only force acting on each ball is gravity. The residual upward force from the hand on each ball is negligible and cancels out when the balls pass each other. Therefore, there is no additional downwards force or residual force from the hand on A.

A Juggler Throws Two Balls Up to the Same Height