Lesson 1.02 Energy: What is it?

Energy is defined as the ability to do work or cause change. There is a direct relationship between matter and energy. Energy holds matter together in the form of bonds. When these bonds are chemically broken down, energy is released. Energy comes in two basic forms: potential energy and kinetic energy. All forms of energy use the SI (International Systems of Units) measurement for energy, which is Joules (J).

Potential Energy: Potential energy is the energy objects have due to position. Potential energy can also be found as stored energy in chemical bonds.

Kinetic Energy: Kinetic energy is energy of motion. Objects often have both kinetic and potential energy. The sum of an object's kinetic and potential energy is often called mechanical energy.

Use Forms of Energy as a resource to see the different types of potential and kinetic energy.

Go to the following interactive sites to learn more about the different types of energy.

• Energy Quest
• What is Energy?

View the following video clip to learn more about the forms of energy. Login Instructions for logging in to Discovery Education Streaming videos. Five Main Forms of Energy (2:41)

Text only version

The Law of Conservation of Energy states that energy can neither be created nor destroyed. It is simply transferred from one form to another. This means that we do not "use up" energy; instead, we use energy and turn it from one form into another. For example, when we turn on our stove, we are using electric energy but we are not using it up. It is simply being turned from one form (electricity) to another (heat).

View the following video clip to learn more about the Law of Conservation of Energy. Login Instructions Energy Changing Forms: The Conservation of Energy (4:41)