Magnetic Fields
What is a magnetic field?
The region around a magnet where magnetic forces can be detected.
What is an electromagnet?
A type of magnet created by running an electric current through a coil of wire.
What is the purpose of a compass?
To show direction using Earth's magnetic field.
What is a ferromagnetic material?
A material that can be magnetized, such as iron or nickel.
Materials like aluminum or copper (these are weakly attracted).
Regions of a magnet where the magnetic force is strongest.
How do magnetic field lines behave around a magnet?
They form closed loops from the north pole to the south pole.
How can the strength of an electromagnet be increased?
By increasing the current, using more coils, or using a better core material.
Why do many cabiners have magnets in the doors?
To create a seal that keeps the door closed.
What is the most common magnetic material used in the core of transformers?
Iron.
How do like and opposite poles of magnets interact?
Like poles repel; opposite poles attract.
What happens to the magnetic field strength as you move away from a magnet?
It weakens as you move farther away.
How can an electromagnet be turned off?
By stopping the current flow.
What is a common household item that uses a magnet to stick to metal surfaces?
Refrigerator magnets.
What material can be easily magnetized and is often used to make permanent magnets? (Hint: Think of Superman)
Steel
What is a permanent magnet?
A magnet that retains its magnetic properties over time.
How can you visualize magnetic field lines?
Using iron filings or a compass.
What is the role of the iron core in an electromagnet?
It amplifies the magnetic field created by the current.
How do maglev trains work?
Using magnetic levitation to reduce friction and allow high-speed travel.
What is a material that does not become magnetic?
Wood, or plastic
What happens when a magnet is broken in half?
It creates two smaller magnets, each with a north and south pole.
What is the shape of the Earth’s magnetic field?
It resembles a dipole, with a north and south pole.
In what everyday devices are electromagnets commonly used?
In motors, MRI machines, and electric bells.
What is a common use of magnets in electronics?
Magnets are used in speakers and headphones to produce sound & magnets are used in hard drives
Which materials do not get magnetized but can still be slightly affected by magnets?
Materials like aluminum or copper (these are weakly attracted).
What is the law of magnetic induction? (How are electromagnets created)
A moving magnet creates an electric current in a nearby conductor.