Forms of Energy

Energy Brief

Energy is the ability to do work or make change. Everything that happens in the world around us involves energy of some kind. The total amount of energy does not change, but energy does change from one form to another.

Energy can be observed as mechanical, light, sound, heat (thermal), and electrical.

Mechanical Energy

Mechanical energy is the energy of motion. Objects have mechanical energy if they are in motion. Examples of mechanical energy include a moving car, a baseball thrown in the air, and a spinning top.

We demonstrate the use of mechanical energy by swinging, swimming, playing with a wind-up toy, riding a bicycle or hammering a nail.

Key word – motion

Sound is the movement of energy through substances in waves. Sound occurs when a force causes an object to vibrate. These vibrations create sound waves.

Sound energy is used in radios, IPods, and for the generation of music. Sound is used for communication by animals including humans. Sound waves can be used in devices such as ultrasound or sonogram machines to produce images. Submarines use sound waves to transmit data underwater.

Key words - vibration, waves

Light is a form of energy that allows us to see. The sun is the ultimate source of light energy (called solar energy) but there are other forms of light energy such as light given off by a candle or an electric bulb.

We can use light energy to see or to power objects such as solar calculators or solar panels that can be used to generate electricity. Plants need light energy to produce their own food.

Key words – Sun, solar

Electrical energy is the movement of charged particles. Electrical energy comes from other forms of energy that are changed. We commonly use this form of energy to power things in our homes.

Examples of electrical energy include objects that run on batteries. Batteries create a flow of particles (electricity) when a circuit is complete. Lightning is an example of a natural form of electrical energy.

Key words- electricity, batteries

Thermal energy is a form of energy that we often refer to as heat energy. Thermal energy is caused by the increased activity of the molecules (or tiny parts) that make up an object. When these particles vibrate very rapidly, heat is produced. Our greatest source of thermal energy is the Sun.

We use thermal energy to heat our water and our homes. Some examples of thermal energy include a campfire, water boiling on a stove, and an oven.

Key word – heat