A child riding on a swing rises to a height 1.0 m above the lowest point. Another child of equal mass whose speed at the lowest point is twice as great will rise
A) to a height which depends on the mass.
B) to the same height.
C) twice as high.
D) four times as high.

Question

Quizplus · Accepted Answer

The energy in a swing is a combination of kinetic energy at the lowest point and potential energy at the highest point. When the speed at the lowest point is doubled, the kinetic energy becomes four times greater (since kinetic energy is proportional to the square of the velocity), allowing the swing to rise four times as high to convert this increased kinetic energy into potential energy.

A Child Riding on a Swing Rises to a Height