7. Magnets Flashcards
At which part of a magnet are the magnetic forces strongest?
The poles of the magnet.
What happens when two magnets are brought close to each other?
They exert a force on each other.
What type of force is exerted if two like poles of a magnet are brought near each other?
A repulsive, non-contact force.
What type of force is exerted if two unlike poles of a magnet are brought near each other?
An attractive, non-contact force.
What is the difference between a permanent magnet and an induced magnet?
A permanent magnet produces its own magnetic field; An induced magnet becomes magnetic when placed in a magnetic field.
What type of force does induced magnetism always cause?
A force of attraction.
What happens when an induced magnet is removed from a magnetic field?
The induced magnet loses most/all of its magnetism.
What is a magnetic field?
The region surrounding a magnet where another magnet or magnetic material experiences a non-contact force.
Give four examples of magnetic materials
- Iron; 2. Steel; 3. Cobalt; 4. Nickel
What can always be said about the force between a magnet and a magnetic material?
It is always attractive.
How does the strength of a magnetic field alter as you move further away from the magnet producing it?
The magnetic field strength decreases the further you move away.
In what direction does a magnetic field point?
In the direction that a north pole would experience a force if placed in the field; From the north-seeking pole to the south-seeking pole of a magnet.
What does a magnetic compass contain?
A small bar magnet that points in the direction of the Earth’s magnetic field.
How can we predict the direction of magnetic field lines around a wire?
Right hand grip
What does your thumb represent in the right hand grip rule?
Direction of current
What do you fingers represent in the right hand grip rule?
Direction of magnetic field lines
What is a solenoid?
A coil of wire with an electric current.
What are the three ways you can increase the magnetic field of a solenoid?
- Increase current
- Increase number of turns in the solenoid
- Add an iron core
How is an electromagnet different to a solenoid?
An electromagnet has an iron core
