Unit 10 Electricity

Unit 10 Electricity

Electricity

Atoms are the building blocks of all matter. We've studied particles. Particles can be atoms, molecules or ions.

Electricity

Atoms are made up of even smaller particles called protons, neutrons and electrons.

Electricity

The main difference between the protons, electrons and neutrons is their electric charge. Electric charge is the property that affects how it behaves around other particles. Protons (+1) Electrons (-1) and Neutrons (no charge)

Electricity

Important to know! When an atom has equal numbers of protons and electrons, the postive charges cancel out the negative charges. So the atom has no charge.

Multiple Choice

On page 485, An atom has three protons, four neutrons with two electrons. What is the charge of the atom?

• +1

• -1

• +2

• -2

Electricity

Particles with the same charge repel (means push away from eachother). Particles with opposite charges attract eachother.

Electricity

Electric charges can build up on objects. This build up is called static electricity. For example making your hair stand up or rubbing a balloon and sticking it to a wall.

Electricity

Have you ever shocked someone with your finger before? Charges stay on objects until they come in contact with something with a different charge. Because electrons repel eachother they spread all over your body. When you touch something the electrons jump from your finger to another object. This is called electrostatic discharge.

Multiple Choice

pge 488 at the bottom: What happens when an object that has a negative charge is placed near an object that has a positive charge?

• The two objects will repel each other

• The two objects will be attracted to each other.

Electricity

Not all electrostatic discharges are small! During a thunderstorm, tiny rain drops or ice particles bump into eachother. These bumps cause electric charges to build in clouds. Positive charges form at the top of clouds and negative charges form at the bottom of clouds. When the difference between these two charges is great enough that's when there is lightning!

Electricity

When electric charges have a path to follow like in a wire, then move in a steady flow. This flow of charges is called an electric current.

Multiple Choice

Bottom of page 490, What do the blue dots on the wire represent?

• matter

• heat

• electrons

Multiple Choice

Bottom of page 490, what is the flow of blue dots called?

• electron flow

• electric current

Electricity

We use electric currents for many things like lights, cooking, computers. We can also get electric current from batteries. Chemical reactions in batteries transform into electrical energy.

Multiple Select

Bottom of page 491, write down three things that use electricity from batteries?

• cell phones

• fridge

• flashlight

• laptop computer

Multiple Select

Bottom of page 491, write down three things that use energy from an energy station.

• electric cars

• lights of homes

• gas cars

• T.V