Niagara falls is a good example of kinetic energy being converted into potential energy?

Niagara Falls is not a good example of kinetic energy being converted into potential energy. While the water at Niagara Falls does possess kinetic energy due to its motion, it is not converted into potential energy as the water flows over the falls. Instead, the kinetic energy of the water is dissipated as heat and sound as the water crashes into the rocks below.

An example of kinetic energy being converted into potential energy would be a ball thrown into the air. As the ball rises, its kinetic energy is converted into potential energy due to its increasing height and thus increasing potential for gravitational potential energy.