Electromagnet Concepts and Applications

What direction do magnetic field lines go?

• From S-Pole to N-Pole

• From N-Pole to S-Pole

• In a circular motion

• From east to west

What is required to make a solenoid?

• A plastic tube

• Insulated wire and electric current

• A wooden stick

• A rubber band

How can the direction of an electromagnet be reversed?

• By changing the core material

• By changing the direction of the current

• By increasing the number of coils

• By using a thicker wire

What material is commonly used for the core of an electromagnet?

• Plastic

• Wood

• Iron

• Glass

What effect does increasing the electric current have on an electromagnet?

• It weakens the electromagnet

• It has no effect

• It strengthens the electromagnet

• It reverses the poles

Why is an iron core better than just a coil in an electromagnet?

• It is cheaper

• It concentrates the magnetic field

• It is lighter

• It is non-conductive

What happens to an electromagnet with a steel core when the current is turned off?

• It loses all magnetism

• It stays magnetic

• It becomes non-magnetic

• It explodes

What is the role of the core in an electromagnet?

• To insulate the wire

• To concentrate the magnetic field

• To provide electricity

• To change the color of the magnet

How can the strength of an electromagnet be increased?

• By decreasing the number of coils

• By using a plastic core

• By increasing the number of coils

• By using a thinner wire

What does iron do that makes it useful in electromagnets?

• It is non-magnetic

• It magnetizes easily

• It is transparent

• It is non-conductive