Magnetism Flashcards
What is a magnetic material?
A magnetic material can only be attracted by a magnet.
What is a magnet?
A magnet can be attracted or repelled by another magnet.
What is a non magnetic material?
A non-magnetic material is not affected by a magnet.
What is a domain?
A domain is a region where magnetic moments of individual electrons are pointing in the same direction.
Which 3 elements are only magnetic?
The only 3 are iron (Fe), nickel (Ni) and cobalt (Co).
Describe the domains in a non magnetic material.
The domains in a non magnetic material are put in random directions.
Describe the domains in a weak magnet.
Most domains in a weak magnet point in the same direction.
Describe the domains in a strong magnet.
All domains in a strong magnet point in the same direction.
What is an induced magnet?
An induced magnet is also known as a temporary magnet and is when a magnetic material/object is magnetised.
What is an electromagnet?
An electromagnet is a type of magnet where the magnetic field is produced by electric current.
What does a moving charge do?
A moving charge always produces a magnetic field.
What does the direction of the magnetic field depend on?
The direction of the magnetic field depends on the direction of the current.
What form is the magnetic fields around a wire of?
The magnetic fields around a wire (carrying the current) is in the form of circles.
What is the trick with your hand to help remember the direction of the magnetic field?
The right hand rule is to use your thumb finger to represent the direction of the electric current, and curl your remaining fingers inwards/ in your direction. This is the direction of the magnetic field in relation to the direction of current.
What is a solenoid?
A solenoid is a coil of wire with current flowing through it, making its magnetic field stronger.
What are the 3 things that help increase the strength of the magnetic field?
1) Add an iron core to the solenoid.
2) Increase the current.
3) Increase the number of turns.
What are some uses of electromagnets?
Lifting scrap cars, a motor, a relay switch etc.
How do relay circuits work?
1) When a current flows through the circuit, an electromagnet is set up.
2) The field attracts an iron armature, whose other end pushes contacts together completing the circuit.
3)When the current is switched off, the contacts close again switching the circuit off.
