Energy can not be created or destroyed, only transformed from one form to another. Water behind a dam changes its potential energy (energy due to its elevated level) into kinetic energy (the turning of the turbine blades) and then into electricity in the generator and then into light and heat in the light bulbs of your house.

Push the button below to see an object that seems to violate this law when it bounces higher than the level from which it's dropped. (It has some energy stored in it before it's dropped)

Balancing Stick
Chaotic Pendulum
Downhill Race
Eddy Currents
Lunar Lander
Pedal Generator
Pendulum Table
Pendulums-Relative Motion
Resonant Pendulum

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