Question

A person throws a ball up into the air, and the ball falls back toward Earth. At which point would the kinetic energy be the lowest?

a point before the ball hits the ground
at a point before the ball hits the ground

at a point when the ball is still rising
at a point when the ball is still rising

when the ball is at its highest point
when the ball is at its highest point

when the ball leaves the person’s hand

Answer 1

The kinetic energy of the ball would be lowest at its highest point when the ball momentarily stops at the top of its trajectory before beginning to fall back towards Earth. At this point, all the kinetic energy has been transformed into potential energy. As the ball falls back down towards Earth, potential energy gets converted back to kinetic energy.