12. Magnetism and the Motor Effect Flashcards
(33 cards)
At which part of a magnetic 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 a magnetic field?
The region surrounding a magnet where another magnet or magnetic material experiences a 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 is the effect when an induced magnetic is removed from a magnetic field?
The induced magnet loses most/all of its magnetism.
Give four examples of magnetic materials.
- Iron
- Steel
- Cobalt
- 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 magnetic producing it?
The magnetic field strength decreases the further you move away.
In what direction does a magnetic field point?
- In the direction of the force that a north pole would experience 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.
What is produced when current flows through a conducting wire?
A magnetic field is produced around the wire.
What determines the strength of the magnetic field around a current-carrying wire?
The magnitude of the current flowing through the wire.
Does a high concentration of field lines mean the field is strong or weak?
Strong
TRUE OR FALSE: Magnetic field lines never cross each other.
True - they never cross, touch or overlap.
How is a plotting compass used to map out a magnetic field?
- Place a compass (containing a needle magnet) on a piece of paper near the field.
- Draw an arrow in the direction the compass points.
- Repeat at different points on the paper.
- Join the arrows to make a complete field pattern.
What is a solenoid?
A coil of wire which when current passes through creates a strong magnetic field.
Describe the magnetic field found inside the solenoid.
Strong and uniform.
Is the field on the outside of a solenoid strong or weak? Why?
Weak.
The fields from each coil cancel out, making the outside field weak.
What is an electromagnet?
- A solenoid with an added iron core.
- Adding the iron core increases the strength of the magnetic field.
What is the motor effect?
When a force is exerted between a magnetic field and a current-carrying conductor placed in that field.
What rule is used to determine the force produced by the motor effect?
Fleming’s Left-Hand Rule
