5th Grade_Unit 8: Magnetism

What is the difference between a bar magnet and an electromagnet?

• Bar magnets and electromagnets are the same types of magnets.

• A bar magnet has same poles that attract. An electromagnet has opposite poles that attract.

• A bar magnet is a temporary magnet that can be turned on and off. An electromagnet is a permanent magnet that is always magnetic.

• A bar magnet is a permanent magnet that is always magnetic. An electromagnet is a temporary magnet that can be turned on and off.

The opposite sides of a magnet where most of the force occurs (north and south)

• Magnet

• Electromagnet

• Magnetic Poles

• Bar Magnet

A piece of iron that has wire wrapped around it to cause an electric current

• Magnet

• Magnetic Poles

• Bar Magnet

• Electromagnet

What is a magnet?

• A piece of iron that has wire wrapped around it to cause an electric current

• A piece of iron that has a magnetic field

• A magnet in the shape of a bar

• The opposite sides of a magnet where most of the force occurs (north and south)

A student was working on an experiment trying to create an electromagnet. How could he create one?

• He could wrap a copper wire around a nail and attach each end of the wire to a battery.

• He could attach a bar magnet to a battery.

• He could wrap yarn tightly around a nail and attach it to a battery.

• He could wrap a piece of string around a nail and attach it to a battery with the other end of the string.

What happens if you try to connect two bar magnets with like poles facing each other?

• The magnets will repel and the magnetic force will push them away from each other.

• The magnets will attract and the magnetic force will pull them together.

• Bar magnets don't have poles.

• Bar magnets are temporary magnets and only attract if turned on.

A crane sometimes uses an electromagnet to lift metal objects. What does a crane operator need to do in order to lift extremely heavy metal objects?

• He will continue attaching bar magnets to the crane until he has enough force to lift the materials.

• He will apply less of a current to the electromagnet to lift heavier things.

• When he is lifting extremely heavy materials, he applies more current to the electromagnet, which will make the magnet stronger and able to lift heavier things.

• He will have to get a different crane for the heavier materials that he is lifting.

A magnet in the shape of a bar

• Bar Magnet

• Magnetic Field

• Magnet

• Magnet Poles

The area around a magnet where the force of magnetism exists

• Magnetic Field

• Bar Magnet

• Electromagnet

• Magnetic Poles

If iron filings were laid out on a plate and a bar magnet was laid on top of them, what would most likely happen?

• The iron filings will only be attracted to the north pole of the magnet.

• Nothing; the iron fillings will not be attracted to the bar magnet.

• The iron filings will disperse to be closest to each end of the bar magnet moving away from it's center.

• The iron filings will only be attracted to the middle of the bar magnet.