The law of conservation of energy states energy cannot be created or destroyed. It can only change from one form of energy to another.

Energy transformation happens when energy is converted into another form. There are many examples of energy transformations in our daily life. A toaster uses the electrical energy running through its wires to create thermal energy—heat—to toast a bagel. When a light switch is turned on, electrical energy heats up the filament inside a light bulb and transforms the energy into light and heat energy that is seen and felt in a glowing light bulb. Food contains stored chemical energy that our bodies must first breakdown to use in order to produce kinetic energy to move.

There is also chemical energy in gasoline. An automobile’s engine creates tiny explosions to release the energy from gasoline, which transforms into kinetic energy used to spin the car’s wheels. Another example of an energy transformation you come into contact with everyday is in a smartphone. Electrical energy flows through the phone and some of it is stored in the phone’s battery. Ultimately, the electrical energy is used to make telephone calls, watch videos, and play games.

Most of the time, it is impossible to watch an energy transformation as it is happening but there are a few examples, such as during a juggler’s performance, where it is possible to see the changes in real time. When a juggler throws a ball into the air, the ball gains potential energy. As the ball falls back down, its potential energy is transformed into kinetic energy. But a juggler is often tossing three or more balls at a time into the air. So, each of the balls cycles through the energy transformation from potential energy to kinetic energy and back again for as long as the juggler keeps the act going.