Unit 10 Lesson 5 How Do We Use Electricity?Apr 10, 2019 · Unit 10 Lesson 5 How Do We Use...

Unit 10 Lesson 5 How Do We Use Electricity?

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Electricity Has Many Uses




• Your life would change if electricity did not exist. • Electrical appliances make life easier. • Devices that use electricity change electrical

energy into other types of energy




Light energy

Sound energy

Heat energy




• The electric motor is a machine found in many

appliances that converts electrical energy into energy of motion.




• What objects in this picture have been replaced with objects that run on electric motors?



Magnets and Magnitism

• A magnet is an object that attracts iron and a few other metals.

• Magnetism is a physical property of matter.




• A magnetic field is the space around a magnet

where the force of the magnet acts.




• Each magnet had two ends, or poles, where its magnetic field is strongest.

• One end is called the south-seeking pole, or S pole.

• The other end is called the north-seeking pole, or N pole.




• Two N poles or two S poles are similar.

• If you place the N poles of two magnets near each other, they push each other away, or repel. Two S poles will push away, too.




• An N pole and an S pole are unlike poles.

• If you place unlike poles of two magnets near

each other, they attract, or pull toward each other.



Electromagnets

• Moving a magnet and a wire near each other produces an electric current.

Hand cranked light bulb



Electromagnets

• A device in which current produces magnetism is called an electromagnet.

• Wrapping a coil of current-carrying wire around an

iron nail makes the nail a magnet.



Electromagnets



Electromagnets

• Electromagnets are very important and useful.

• Every electric motor contains at least one electromagnet.

• Electromagnets can be found in telephones, doorbells, speakers, computers, doctors use electromagnets to take picture of the inside of the body.



Electromagnets



Generating Electricity •In a hydroelectric dam, the mechanical energy of falling water can be converted to electrical energy.



Generating Electricity

• Energy stations may use water, coal, or atoms to produce electricity.




• Renewable resources are resources that will never run out. Sunlight and falling water are examples.

• Coal is a limited, or nonrenewable, resource. It

will eventually run out. • Conserving electricity helps conserve resources

that will eventually run out.




• Wind mills can generate electricity.




• A device that converts mechanical energy to electrical energy is called a generator.

Unit 10 Lesson 5 How Do We Use Electricity?Apr 10, 2019 · Unit 10 Lesson 5 How Do We Use...

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