Vocabulary in Action
What object has north and south poles and attracts iron?
A magnet.
What tool uses a magnetic needle to help people find directions?
A compass.
What type of magnet uses electric current to produce a magnetic field?
An electromagnet.
You need a magnet to pick up a latch. Should you make the latch from iron or wood?
Iron
You want to compare how many paper clips two magnets can lift. What should you count?
you would MEASURE - The number of paper clips each magnet lifts.
You turn a magnet so its north pole faces a different direction. What vocabulary word describes the way it is positioned?
Orientation
What force holds a magnetic purse clasp closed?
Magnetic attraction.
What can you switch on and off in an electromagnet to control its magnetic force?
The electric current.
A cabinet has a magnet on its frame. What could you attach to the matching spot on the door so it stays shut?
An iron or magnetic steel plate, or a magnet with the opposite pole facing the frame magnet.
You are testing how distance affects magnetic force. What should you change: the distance between the magnets or their color?
The distance between the magnets.
What vocabulary word means “how one thing is linked to another”?
Relationship
Why does a compass needle line up roughly north–south?
Its needle is a tiny magnet that aligns with Earth’s magnetic field.
A student builds an electromagnet using a battery, insulated wire, and an iron nail. How should the wire be arranged around the nail?
Wrapped around the nail in a coil.
Car 1 is behind Car 2. Car 1’s front magnet has its north pole facing Car 2. Which pole should face backward on Car 2 so Car 1 can push it without touching?
North. Like poles repel.
A balloon is rubbed 3, 6, and 9 times. What could you measure to compare how strongly it attracts small paper pieces?
The number of paper pieces it picks up after each trial.
A magnet pulls a toy car forward. Identify the force and the interaction in this example.
The force is the magnetic pull. The interaction is the magnet affecting the car’s movement.
What is ferrofluid, and what can happen to its shape near a strong magnet?
A liquid containing tiny magnetic particles. It can form spikes near a strong magnet.
Why does a simple nail electromagnet usually drop its paper clips when a wire is disconnected from the battery?
The current stops, so the coil’s magnetic field disappears and the nail loses most of its magnetism.
An outside magnet must slide a latch inside a thin wooden model door. Name two features the latch needs.
It must be made from a material attracted to a magnet, such as iron, and it must be able to slide freely.
You compare two magnets by counting the paper clips they lift. Name two things you should keep the same to make the test fair.
Use the same kind of paper clips and the same pickup method, including the starting distance.
Describe the relationship between distance and magnetic force when two magnets move farther apart without turning.
As distance increases, the magnetic force becomes weaker.
Some MagLev trains use magnetic repulsion to float above their tracks. Explain how repulsion helps lift the train.
Magnetic forces push the train upward, supporting it above the track without wheels touching the track.
Explain how a crane operator uses an electromagnet to pick up, move, and release iron scrap.
Turn the current on to attract the scrap, keep it on while moving the load, and turn it off to release the scrap.
Why is an electromagnet more useful than a permanent magnet for a crane that must repeatedly pick up and drop iron?
An electromagnet can release the iron when its current is switched off. A permanent magnet keeps attracting it and needs another way to separate the load.
Describe two different classroom tests you could use to compare magnet strength.
Compare how many identical paper clips each magnet lifts, and measure the farthest distance at which each magnet starts moving the same paper clip. Keep other conditions the same.