Unit 10 lesson 1 what is electricity

Unit 10 Lesson 1 What Is Electricity?

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All Charged Up• Atoms are the building blocks of matter.

• Atoms are so small you cannot see them with your eyes alone. They are made of smaller particles called protons, neutrons, and electrons.

• Electric charge is a property of a particle that affects how it behaves around other particles.



All Charged Up• Protons have a positive charge (+1).

• Electrons have a negative charge (–1).

• Neutrons are neutral. They have no charge.



All Charged Up• When an atom has equal numbers of protons and

electrons, the charges cancel each other.

• Atoms sometimes gain or lose electrons. Gaining or losing electrons will change the positive or negative charges of the atom.

• If an atom gains electrons, it will have a negative charge. If a neutral atom loses an electron, it will have a positive charge.



Opposites Attract• Particles with the same charge repel, or push

away from, one another.

• Particles with opposite charges attract one another, or pull together.

• Static electricity is the buildup of electric charges on objects.

• Static means “not moving.”



Opposites Attract• Why does static electricity cause your hair to

stand “on end”?



Lightning Strikes• Static charges stay on an object until it comes

close to an object with a different charge.

• An electrostatic discharge happens when electrons jump from an object with a negative charge to an object with a positive charge.



Lightning Strikes• Raindrops and ice particles bump into each other

during a thunderstorm, causing an electric charge to build in the clouds.

• Positive charges form at the top of a cloud and on the ground. Negative charges form near the bottom of the cloud.

• When the difference in charge between a cloud and the ground is great enough, lightning occurs.

• Lightning is a huge electrostatic discharge.



Lightning Safety

• Stay inside and turn off electrical appliances.

• Stay away from windows.

• If you can’t get inside, wait in a car with a metal roof.

• Listen to the weather forecast for updates about thunderstorms.

• Make a plan in case a thunderstorm develops.



Current Events• When electric charges have a path to follow, they

move in a steady flow called an electric current.

• Chemical reactions in batteries can provide a flow of electrons.

• An electricity generating station is another source of electric current.



Current Events• What is the purpose of the insulator on the wire

shown below?



Current Events• Moving electric charges are more useful than

static electricity.

• Electrons can be made to move through a wire. They make up an electric current. You can use electric current to do many kinds of work.

• Electric currents for homes, schools, and businesses come from energy stations. These stations change chemical, nuclear, or mechanical energy into electrical energy.

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Unit 10 lesson 1 what is electricity