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Unit 10 lesson 1 what is electricity
- 1. Unit 10 Lesson1 What Is Electricity? Copyright © Houghton Mifflin Harcourt Publishing Company
- 2. Unit 10 Lesson1 What Is Electricity? 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. Copyright © Houghton Mifflin Harcourt Publishing Company
- 3. Unit 10 Lesson1 What Is Electricity? All Charged Up • Protons have a positive charge (+1). • Electrons have a negative charge (–1). • Neutrons are neutral. They have no charge. Copyright © Houghton Mifflin Harcourt Publishing Company
- 4. Unit 10 Lesson1 What Is Electricity? 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. Copyright © Houghton Mifflin Harcourt Publishing Company
- 5. Unit 10 Lesson1 What Is Electricity? 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.” Copyright © Houghton Mifflin Harcourt Publishing Company
- 6. Unit 10 Lesson1 What Is Electricity? Opposites Attract • Why does static electricity cause your hair to stand “on end”? Copyright © Houghton Mifflin Harcourt Publishing Company
- 7. Unit 10 Lesson1 What Is Electricity? 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. Copyright © Houghton Mifflin Harcourt Publishing Company
- 8. Unit 10 Lesson1 What Is Electricity? 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. Copyright © Houghton Mifflin Harcourt Publishing Company
- 9. Unit 10 Lesson1 What Is Electricity? 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. Copyright © Houghton Mifflin Harcourt Publishing Company
- 10. Unit 10 Lesson1 What Is Electricity? 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. Copyright © Houghton Mifflin Harcourt Publishing Company
- 11. Copyright © HoughtonMifflin Harcourt Publishing Company Unit 10 Lesson 1 What Is Electricity? Current Events • What is the purpose of the insulator on the wire shown below?
- 12. Unit 10 Lesson1 What Is Electricity? 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. Copyright © Houghton Mifflin Harcourt Publishing Company