topic 7: magnetism and elctromagnetism 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,no contact force
What type of force is exerted if two unlike poles of a magnet of brought each other?
an attractive ,noncontact force
What is the difference between a permanent magnet and an induced magnet?
A permanent magnet produces its own magnetic field
An induce 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 magnet field?
The region surrounding a magnet where another magnet or magnetic material experiences a noncontact force
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 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 magnetic field
what is produced when the 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
The distance from the wire
What is a solenoid?
A coil of wire which when current passes through creates a strong magnetic field
Describe the magnetic field found inside a solenoid
Strong and uniform
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 current carrying conductor placed in that field
what rule is used to determine the force experience due to the motor effect
Flemming’s left hand rule
when using Flemming‘s left-hand rule, what does the forfinger represent?
The forfinger points in the direction of the magnetic field
when using Flemming’s left hand rule what does the second finger represent?
The second finger points in the direction of current flow in the conductor
what factors affect the size of the force on a current carrying wire in a magnetic field?
The magnitude of the current flowing through the conductor
The strength of the magnetic field that the conductor is placed in
if the direction of a current in a current carrying wire placed in a uniform magnetic field is reversed, what happens to the force?
 the direction of the forces is reversed