Transcript Document

Unit 5 Lesson 3 What Is Electricity?
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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.
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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.
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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.
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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.
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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.
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Unit 5 Lesson 3 What Is Electricity?
Opposites Attract
• Why does static electricity cause your hair to
stand up?
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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.
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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.
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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.
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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.
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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
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.
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