Understanding Electromagnets

Multiple Choice

What is an electromagnet?

• A permanent magnet that retains its magnetism

• A type of magnet that is created by an electric current

• A magnet that is made from natural materials

• A magnet that does not require electricity to function

Multiple Choice

Which of the following is a component of an electromagnet?

• A wooden core

• A copper wire coil

• A plastic casing

• A rubber band

Electromagnets are made of a conductive wire, a conductive metal core, and a battery.

If the core is not a conductive metal, the electromagnet will not create a magnetic field.

The coil creates the magnetic field when attached to the battery. More loops = stronger magnetic field.

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Components of an Electromagnet:

Multiple Choice

Describe the role of the coil in an electromagnet.

• The coil is used to store energy.

• The coil is used to conduct electricity and create a magnetic field.

• The coil is used to insulate the magnet.

• The coil is used to cool down the magnet.

Multiple Choice

Explain how the core material affects the strength of an electromagnet.

• The core material does not affect the strength of an electromagnet.

• A non-magnetic core increases the strength of an electromagnet.

• A magnetic core, like iron, increases the strength of an electromagnet.

• A plastic core is the best for increasing strength.

​When the wire is connected to both the positive and negative ends of the battery, electricity flows through the wire.

This flow of negative particles turns the metal core into a magnet.

When the wire is disconnected, the metal stops acting like a magnet.

How an Electromagnet Works

Multiple Choice

What happens to an electromagnet when the electric current is turned off?

• It becomes a permanent magnet.

• It loses its magnetism.

• It becomes stronger.

• It changes its polarity.

​Generators for when the power goes out

​MRI machines at the hospital

​Cranes at the junkyard

Multiple Choice

Identify one application of electromagnets.

• In refrigerators to keep the door closed

• In electric bells to produce sound

• In solar panels to generate electricity

• In wind turbines to capture wind energy

Multiple Choice

Which of the following is NOT an application of electromagnets?

• MRI machines in hospitals

• Electric motors

• Compasses

• Cranes for lifting heavy metal objects

Multiple Choice

How can the strength of an electromagnet be increased?

• By decreasing the number of turns in the coil

• By using a non-magnetic core

• By increasing the electric current

• By using a thinner wire

Multiple Choice

Which factor affects the strength of an electromagnet?

• The color of the wire

• The number of turns in the coil

• The shape of the core

• The type of battery used

Multiple Choice

How does increasing the electric current affect an electromagnet?

• It decreases the strength of the electromagnet.

• It has no effect on the electromagnet.

• It increases the strength of the electromagnet.

• It changes the polarity of the electromagnet.