Unit 5 Lesson 3 What Is Electricity? Copyright © Houghton Mifflin Harcourt Publishing Company 1

Unit 5 Lesson 3 What Is Electricity? Florida Benchmark SC.5.P.10.3 Investigate and explain that an electrically-charged object can attract an uncharged object and can either attract or repel another charged object without any contact between the objects. Copyright © Houghton Mifflin Harcourt Publishing Company 2

All Charged Up Atoms are the building blocks of matter. Unit 5 Lesson 3 What Is Electricity? All Charged Up Atoms are the building blocks of matter. Atoms are made of 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

All Charged Up Protons have a positive charge (+1). Unit 5 Lesson 3 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 5 Lesson 3 What Is Electricity? All Charged Up When an atom has equal numbers of protons and electrons, the charges cancel each other. Atoms can gain or lose electrons. A gain or loss of electrons will change the charge of the atom. If an atom gains electrons, it will have a negative charge. If it loses electrons, it will have a positive charge. Copyright © Houghton Mifflin Harcourt Publishing Company 5

Unit 5 Lesson 3 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. Copyright © Houghton Mifflin Harcourt Publishing Company 6

Unit 5 Lesson 3 What Is Electricity? Opposites Attract Why does static electricity cause your hair to stand up? Copyright © Houghton Mifflin Harcourt Publishing Company 7

Unit 5 Lesson 3 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 5 Lesson 3 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. 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

Lightning Safety Stay inside and turn off electrical appliances. Unit 5 Lesson 3 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. Copyright © Houghton Mifflin Harcourt Publishing Company 10

Unit 5 Lesson 3 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

Unit 5 Lesson 3 What Is Electricity? Current Events What is the purpose of the insulator on the wire shown below? Copyright © Houghton Mifflin Harcourt Publishing Company 12

Unit 5 Lesson 3 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. Electric currents power your home. Copyright © Houghton Mifflin Harcourt Publishing Company 13