Magnets And Electromagnets Flashcards
Two poles that are the same will…
Repel
Two poles that are different will…
Attract
What does the needle of a compass line up with?
The magnetic field of a magnet
Why does a compass needle always point in the same direction wherever you point it?
It will point towards the magnetic north as it is in the earth’s magnetic field
How can you make an electromagnet?
When a current flows through a wire, it produces a magnetic field around it. You can make an electromagnet using a coil of wire with a current flowing through it
How can you make an electromagnet using a coil of wire and an iron bar?
1.Put the coil of wire around the bar, strip ends of wire.
2. Switch on currents connected to end of coil.
What is a solenoid?
A solenoid is a coil of wire which can have a current flowing through it to make an electromagnet.
What are 3 things that can affect the strength of a magnet?
- The number of turns/ loops on the coil
-Increase the electric current - Use a stronger magnetic material in the core
Why would you use an electromagnet instead of a permanent magnet for some functions?
-You can switch electromagnets on an off
- You can make electromagnets stronger
Name some devices that use electromagnets in them
- electric bell buzzer
- circuit breaker
- Loudspeakers
What makes something magnetic?
Magnetic materials contain property that we call magnetic domains. These domains point in all sorts of directions but if you get all domains to face the same direction then it will increase the affect of magnetism
What is an example of a permanent magnet?
A bar magnet
Name 3 magnetic materials
- Iron
- Steel
- Nickel
