electricityelectricity. what do atoms contain? charged particles

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ElectricityElectricityElectricityElectricity

What do atoms contain?

•Charged particles

What charge does a proton have?

•Positive

What charge does an electron have?

•Negative

What charge is an atom with more electrons

than protons?

•Negative Charge

What do atoms with opposite charges

do?

•Attract each other

Where are electrons located?

•Moving around the outside of the nucleus

What is a neutral atom?

•The number of protons equals the number of electrons. NO CHARGE

What if the number of protons and

neutrons are not equal?

•Then there will be some kind of charge.

What does the movement of

electrons produce?

•Produces electricity

What is a form of energy produced by moving

electrons, also known as electrical energy?

•Electricity

What is electricity used for?

• Run lights in homes, schools, offices, street and traffic lights

• Toaster and electric ovens produce heat from electricity

• Homes are heated by electricity• Radios

What are the four types of energy can electricity

change into? Give examples.

• Light Energy• Mechanical Energy• Heat Energy• Sound Energy

What is a magnet made by coiling a wire around a piece

of iron and running electricity through the wire?

•electromagnet

How does electricity make magnetism?

•When electricity flows through a wire, it makes a magnetic field around the wire.

When can electromagnets be

very useful?

•They can be turned on and off

Where else can electromagnets be used?

•Hold heavy fire doors open•For cranes in steel recycling centers

•Lift metal objects off of ships

What are the two main parts of a

motor?

•The coil of wire and a magnet

How is an electric motor like an electric generator?

•They both involve a spinning coil

How is an electric motor different from an

electric generator?

•The electric generator=Turns spinning motion (mechanical energy) into electricity

•The electric motor=Turns electricity into a spinning motion

What is the buildup of charges when the number of protons and electrons are no longer

equal?

•Static electricity

Why do clothes stick together when you pull them out of a

dryer? •When clothes are in the dryer

and rub together, some have a positive and some have a negative charge.

•This causes them to stick together.

What is the shock you feel when you pull off a

sweater?

•Static discharge

Why is there a static discharge?

• This is when electrons are moving around to try and balance out the charges and make them neutral.

How does lightning have a static discharge?

• Collisions between water droplets in a cloud cause the drops to become charged.

• Negative=Bottom• Positive=Top• Electrons jump causing lightning

What causes thunder?

•The lightning heats the air, causing it to expand. As cooler air rushes in to fill the empty space, you hear thunder.

How is static electricity considered potential

energy?

•Energy is stored and a static charge builds up.

Why isn’t a static discharge a good energy source since it

is kinetic energy?

•A very short burst

•There needs to be a steady flow of electrons.

When electrons have a path to follow, they will move in a

steady flow instead of building up a static

discharge. This is known as?

•Electric Current

Electricity that is a kind of kinetic energy as stated

above is considered?

•Current Electricity

What is needed to keep currents

flowing?

•A constant supply of electrons is needed.

What is electrical pressure known

as?

•Volts

How many volts can one lightning strike have?

•1 billion volts of electricity

What is the rate at which electric current flows

measured in?

•Amps

What do we call the measure of electric energy used by an

electric device every second?

•Watts

Since watts are very small units, what is electrical

use measure in?

•kilowatts

How many watts is one kilowatt?

•One kilowatt = 1,000 watts

What should wires with electricity flowing

through them have on them and why?

•Plastic around wire to work as an insulator against the electrical current

What is the path an electric current follows?

•Electric circuit

What two things does an electric circuit need

for a current to flow?

1.Needs a source of current, or electrons

2.Circuit has to be complete

What if there is a break in the circuit?

•The current will not flow.

What happens when a circuit is on?

•The circuit is complete•Lights come on

What happens when a circuit is off?

•Breaks the flow of current

•Light goes out

What circuit has only one path to

follow?

•Series Circuit

What will happen if you remove any part of a

series circuit?

•Breaks the circuit, and current stops flowing

What would it be like to have series circuits at

home?

• All electric devices would have to be switched on all the time

• If you unplugged a radio, all the lights in your home would go out!

When was series circuits used?

•Light signs, scoreboards, string of Christmas lights

What circuit is more convenient because it has more than one path for currents to

follow?

•Parallel circuit

Give some examples of parallel circuits.

•You are able to turn certain items off and on without turning everything in a building off and on

Why does parallel circuits have a huge

advantage over series circuits?

• If one appliance is turned off, the others stay on.

• You can connect more devices by using a parallel circuit.

• In a series circuit, lights will become dimmer if too many lights are added.

What do engineers have to do when they are designing a

new design for a building or item?

•Draw diagrams

What is shown in a simple series circuit

diagram?

•Light bulb and a battery

What is shown in the circuit diagram of car

electrical circuits?

•Many different symbols and wires

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