Chapter 13: Electricity and Magnets

Lesson 1: What Is Electricity?

VOCABULARY

Static electricity

Current electricity

Circuit

Static Electricity On a cold day, you may see a person’s hair stand up straight. The reason the hair stands up is static electricity. Static electricity is an electric charge that builds up in an object. Lightning is one example of static electricity. A static charge builds up in a cloud, and then current electricity moves to the ground in the form of a lightning flash. You may even hear a crackling noise.

What happens when you plug a lamp into a wall outlet? Electricity flows from wires in the wall through the plug and into the lamp’s wires. Electricity that moves through a wire is current electricity.

A lamp’s bulb glows only when there is a closed circuit. A circuit is a path that electricity follows. Electricity moves from the wall outlet, through the lamp, and back to the wall.

People use current electricity to light, heat, and cool homes, to run motors, and to cook food. What other things do you know of that use electricity?

MAIN IDEA AND DETAILS What is current electricity?

How Electricity Moves

Electricity moves through some things but not through others. Something that electricity moves freely through is called a conductor. Copper wire is a good conductor.

Something that electricity will not move through easily is called an insulator. Wood and plastic are examples of insulators. Electricity can be dangerous, so people use insulators to stay safe.

MAIN IDEA AND DETAILS    What is a conductor? What is an insulator?