Illustration of a ball on a ramp, changing colour to show the relationship between potential energy and kinetic energy. At the start the ball is stationary on the ground and has neither potential nor kinetic energy, and is grey. A force (blue arrow) then lifts it up against gravity, giving the ball potential energy (blue), due to the force of gravity accelerating it down towards the floor. As it rolls down the ramp its speed increases, meaning its kinetic energy rises and it turns purple. As it hits the floor it is travelling at its maximum speed and its kinetic energy is highest, and the ball is red. The gravitational potential energy has been converted to kinetic energy.