Brainpop: Electromagnets

What effect will the north pole of one magnet have on the north pole of another magnet?

• Repulsive

• Attractive

• Combative

• No effect

Why are paperclips attracted to magnets?

• They contain silver

• They contain aluminum

• They contain tin

• They contain iron

What is the simplest requirement for an electromagnet?

• A coil of electrified wire

• A coil of electrified wire wrapped around an iron core

• A bar magnet and a power source

• A length of electrified wire

Where does a magnetic field occur in relation to an electrified wire?

• At either end, but not in the middle

• Only on the side closest to the source of electricity

• Around the entire length of the wire

• Only on the side furthest from the source of electricity

How would you compare the magnetic field generated by a simple length of wire to the magnetic field generated by a coil of wire?

• The coil generates a stronger magnetic field.

• The coil generates a weaker magnetic field.

• The field generated by the coil has a different polarity than the field generated by the length of wire.

• The coil generates a field that attracts iron objects; the length of wire generates a field that attracts silver objects.

Which of the following depicts the strongest solenoid?

• A

• B

• C

• D

How do electromagnets differ from regular magnets?

• They can be turned on and off

• Their polarity can be reversed

• Their strength can be changed

• All of the above

How might an electric motor be used in a washing machine?

• To make water flow into the machine

• To make the machine spin

• To add the correct amount of soap

• To make water drain out of the machine at the end of the cycle

When will a circuit breaker trip, or turn off?

• When the polarity of the electromagnet inside it is reversed

• When any type of current passes through it

• When a very strong current passes through it

• When a special on/off switch is activated

To change the polarity of an electromagnet, you would:

• Reverse the current's direction

• Reverse the direction in which the coil is wound

• Turn the battery, or other power source, upside-down

• Remove the iron core from within the coil of wire