In this topic you will learn how electric energy can be changed into other forms of energy.

An energy transfer is a change of energy from one form to another. For example, light energy normally radiates, or travels, in all directions from a light bulb. If the bulb is painted black, the black paint will absorb the energy of the light. The bulb will get hotter and hotter as it absorbs more and more light energy.

Electric energy can be changed to heat energy. Coils of wire in devices like irons or light bulbs are good resistors. These wires are looped into coils. This allows a long wire to fit into a small space. Some of the electrical energy that passes through these coils is changed to heat energy. The more coils an appliance has, the hotter it can get.

Electric energy can be changed to sound energy. Speakers in radios, telephones, CD players, and other devices produce sound. A coil of wire surrounds a magnet in a speaker. Current moving through the wire causes the magnet to move. The moving magnet pushes the cone of the speaker. The vibration of the cone in a speaker creates a sound pattern.

Electric energy can be changed to chemical energy. Some batteries are rechargeable because the chemical reactions in them can be reversed. A battery recharger needs to be plugged into an electrical outlet. This causes the chemical reaction to be reversed.

An electric motor changes electric energy into mechanical energy. The electric energy can make a motor spin, which in turn can make a car's wheels turn.

Electric energy can also be turned into light energy. A television changes a pattern of electric energy into a pattern of light energy. A signal or pattern of electricity comes from a cable or antenna. This signal makes the pattern on the television screen.

It is important to know safety rules when using electric energy because electric devices can be dangerous if they are not used properly.

Understanding how to change energy is useful because much of the energy we use is transformed from one form to another.