Magnetism Flashcards
Name the two types of magnets.
- Bar magnets.
2. Horseshoe magnets.
Define “alloy”.
A mixture of two or more metals.
What happens if you cut a magnet in half?
It will remagnetise and the two ends of each magnet will polarise again.
What is the law of magnetism?
Like poles repel;
Unlike poles attract.
Magnetic materials must be ______________ before they become magnets. Their __________ are pointing in different directions and must be aligned.
Magnetised.
Domains.
Name two ways you can magnetise a magnetic material.
- Stroking it with a magnet.
2. Placing it near a strong magnet.
Name 3 ways in which you can demagnetise a magnet material.
- Heating it up.
- Hammering it continuously.
- Sending an alternating current (AC) through it.
Define “magnetic field”.
The space surrounding a magnet where the effect of the magnet can be defected.
What components do you need in order to build an electromagnet?
- A cell.
- Copper wire.
- An iron nail.
When an electric current flows through a conductor, a m_______ f______ is created around it.
Magnetic field.
Define “solenoid”.
A wire with many circular coils that carry a current.
EXTENSION:
The current creates a magnetic field in and out around the solenoid.
What does a relay switch do?
A relay switch uses a small current in one circuit to activate an electromagnet that closes the 2nd circuit with a big current.
What does a reed switch do?
A reed switch uses 2 pieces of magnetic material (reeds) with a gap in between, enclosed in a glass tube.
Name 3 magnetic materials.
Iron, nickel, cobalt.
