Energy Transformation and Conservation

Energy transformation, or conversion, occurs when energy is changed from one form to another. We rely on energy transformations for many important things. For example, the chemical energy of gasoline converts to thermal energy when it is burned, and then changes to mechanical energy to move a car. When a drill is plugged in, electrical energy is transformed to mechanical energy and sound.

When energy is transformed, some of the original energy is converted to thermal energy. Imagine a gyroscope that is spinning due to mechanical energy. It experiences friction with the surface it is spinning on and creates thermal energy. Eventually, the gyroscope will stop spinning when its mechanical energy has been completely transformed into thermal energy.

As energy is transformed, the total amount of energy does not change. The law of conservation of energy states that energy cannot be created or destroyed. A roller coaster car is lifted to the top of a steep hill using mechanical kinetic energy. At the top, it has a large amount of potential energy. As it moves down the hill, it has kinetic energy again. However, some of its energy is converted to sound and to thermal energy due to friction. As it continues to move, the car’s energy decreases as it is transformed to other types of energy, but the total amount of energy does not change.