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Science Study Guide
Magnets and Electricity
These concepts, vocabulary and experiment results are all important for understanding magnetism,
electricity and electromagnetism.
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Science vocabulary sheets: magnet, magnetic force, magnetism, and non- magnetic,
Attract/attraction and repel/repulsion, magnetic poles, field lines.
Magnets can make objects move without direct contact between the object and the magnet.
● Magnets pull on (attract) objects made of iron or have iron in them.
Materials can be identified using magnets, and mixtures of materials can be separated
using magnets.
● Magnets can pull (attract) or push (repel) other magnets.
● A magnet’s push or pull can cause a magnetic object or another magnet to move
without direct contact.
● A permanent magnet cannot be “turned on and off”.
●The magnetic field is strongest around the ends of a magnet.
Objects that are magnetic will be pulled by a magnet, for example: paper clips, steel wool, tack.
Some metals are nonmagnetic, for example aluminum, brass, copper, silver and gold.
Magnetism can travel through many materials, for example wood, paper, plastic, water, and the air.
The Law of Magnetic Attraction:
Opposite poles attract (north and south); Like poles will repel (north and north / south and south)
● The earth is a giant magnet. The magnetic fields around the poles and solar wind
particles create the Aurora Borealis (Northern/Southern lights).
● A compass points North because of the earth’s magnetic fields.
Electrical and magnetic energy can be transferred and transformed.
Vocabulary Current, circuit, conductor, insulator, electric motor, generator, battery, open and closed
circuit
● Electricity in circuits can be transformed into light, heat, sound and magnetic effects.
● Batteries and wires can transfer energy to light a light bulb, heat a wire, power a buzzer, and
create an electromagnet.
In a circuit, the electrical current travels through a conductor, to the device that it powers, and
back to the source to create a closed circuit.
To create a closed circuit with one battery, one wire and one lightbulb, the current must travel
from the positive terminal of the battery, through the wire, to the side ( screwthread) of the
light bulb when the foot is touching the negative terminal of the battery.
In an open circuit, there is a break in the circuit which stops the flow of electricity.
Some causes of an open circuit: wire disconnected, bulb broken or unscrewed, power source not
connected, switch open.
Examples of electricity transformed into light energy: lightbulbs, flashlights, strings of lights.
Examples of electricity transformed into heat energy: hair dryer, iron, electric oven/stove.
Examples of electricity transformed into sound energy: radio, buzzer, hearing aid, telephone.
Examples of electricity transformed into magnetic effects: junkyard crane, maglev train, MRI.
Sources of electric power in your home are: an outlet, a battery, a home generator.
Electromagnets can be very powerful. Since they are formed using an electric current,
they can also be turned on and off.
An electromagnet can be created by winding a wire around a metal rod and running electric current
through the wire.
Conductors are made out of metals, although electricity can travel through water and air.
Insulators stop or slow down the flow of energy. Some examples of good insulators are:
plastic, rubber, glass, Styrofoam.
Examples of electricity that travels though the air: lightning and static electricity.
Static electricity is the build up of electrical charges that build up and discharge as a shock,
or cause static cling.