GCSE Edexcel Physics 12.1 - Magnetism
Study these flashcardsFree · spaced repetition · iPhone, Android, Mac & web
All cards
1
Unlike magnetic poles will…
Attract
2
Like magnetic poles will…
Repel
3
Two north magnetic poles will…
Repel
4
Two south magnetic poles will…
Repel
5
A north magnetic pole and a south magnetic pole will
Attract
6
What is the difference between a magnetic and a non-magnetic material?
Magnetic materials are attracted to magnets, non-magnetic materials are not
7
Examples of magnetic materials (5)
Elements: Iron, Cobalt, Nickel
Alloys: Steel, Bronze
Alloys: Steel, Bronze
8
How can you identify whether a material is a magnet or not?
Magnetic materials which are not magnets always attract to other magnets
The material is a magnet if it can be attracted and repelled by other magnets
The material is a magnet if it can be attracted and repelled by other magnets
9
What is a permanent magnet?
Made out of a permanent magnetic material (like steel)
It will not lose its magnetism
Produces its own magnetic field
It will not lose its magnetism
Produces its own magnetic field
10
What is an induced magnet?
When a magnetic material is placed in a magnetic field, it is temporarily turned into a magnet (induced magnetism)
When it is removed from the magnetic field, it loses its magnetism
When it is removed from the magnetic field, it loses its magnetism
11
What is the polarity of the induced magnet?
Magnetic materials/induced magnets are always attracted to the magnet
The end closest to the magnet will have opposite pole
The end closest to the magnet will have opposite pole
12
What is the polarity of the induced magnet?
Magnetic materials/induced magnets are always attracted to the magnet
The end closest to the magnet will have opposite pole
The end closest to the magnet will have opposite pole
13
Shape and strength of magnetic field around a bar magnet
Field lines going from north to south pole
14
Shape of magnetic field in gaps between opposite poles
Uniform field (only inside the gap)
Straight parallel lines going from north pole to south pole
Straight parallel lines going from north pole to south pole
15
How is the strength of a magnetic field represented with field lines?
Lines closer together = stronger field
Lines further apart = weaker field
Lines further apart = weaker field
16
Strength of a magnetic field around a bar magnet?
Field is strongest at the poles where the field lines are closest
The greater the distance, the weaker the magnetic field
The smaller the distance, the stronger the magnetic field
(Look at how far apart field lines are closer and further away from the bar magnet)
The greater the distance, the weaker the magnetic field
The smaller the distance, the stronger the magnetic field
(Look at how far apart field lines are closer and further away from the bar magnet)
17
How does the strength of a magnetic field change in a uniform field (in gaps between opposite poles)?
It doesn’t
Strength of magnetic field is the same at all points
Field lines are same distance apart at all points
Strength of magnetic field is the same at all points
Field lines are same distance apart at all points
18
Field lines for two attracting bar magnets
19
Field lines for two repelling bar magnets
20
What can you use to show the shape and direction of a magnetic field around a bar magnet?
Iron filings or plotting compasses
21
5 Step process for using plotting compasses to show shape and direction of magnetic field
1. Draw a dot at corner of magnet
2. Place a plotting compass on the dot, and draw dot at other end of compass needle
3.Move compass to new dot and repeat
4. Link the dots, (direction of field is the same as direction of plotting compass)
5. Repeat to create multiple magnetic field lines.
2. Place a plotting compass on the dot, and draw dot at other end of compass needle
3.Move compass to new dot and repeat
4. Link the dots, (direction of field is the same as direction of plotting compass)
5. Repeat to create multiple magnetic field lines.
22
Describe how you could show the Earth has a magnetic field
Using a compass - the needle will always point north
23
Magnetic field when current flows through a wire
Right hand thumb rule
Thumb in direction of current, curled fingers are direction of field lines
Thumb in direction of current, curled fingers are direction of field lines
24
What can be used to investigate the magnetic field around a conducting wire?
Plotting compasses
25
Relationship between magnetic field strength and distance in a conducting wire
As distance from wire increases, magnetic field strength decreases
(Field lines become more spaced out)
(Field lines become more spaced out)
26
Relationship between magnetic field strength and current in a conducting wire
As current increases, magnetic field strength increases
(Field lines closer together)
(Field lines closer together)
27
What happens to the magnetic field when you reverse the current in a conducting wire?
The direction of the magnetic field is reversed
28
Direction of current (Dots and Cross)
Dot - Current flowing out of the page
Cross - Current flowing into the page
Cross - Current flowing into the page
29
How can you make a solenoid
Loop a wire into coils + current
30
A solenoid is an example of…
An electromagnet
31
How can you increase the strength of a magnetic field around a wire?
Coil the wire into a solenoid
(Increase the current - less effective)
(Increase the current - less effective)
32
What happens to the magnetic fields of individual turns in a solenoid?
Inside - the magnetic fields add together to form a strong uniform field
Outside - The fields cancel out so field is weaker
Outside - The fields cancel out so field is weaker
33
Solenoids have a similar magnetic field to bar magnets
Which pole does this end of the solenoid behave like?
Which pole does this end of the solenoid behave like?
North pole
Look at solenoid from that end
Anticlockwise current = North pole
Look at solenoid from that end
Anticlockwise current = North pole
34
Solenoids have a similar magnetic field to bar magnets
Which pole does this end of the solenoid behave like?
Which pole does this end of the solenoid behave like?
South pole
Look at solenoid from that end
Clockwise current = South pole
Look at solenoid from that end
Clockwise current = South pole
35
What happens to the poles at the ends of a solenoid if current switches direction
The poles switch
36
How can you increase the strength of the magnetic field produced around a solenoid?
Increase the current
Add more turns
Add an iron core in the centre
Add more turns
Add an iron core in the centre
37
What happens when you place an iron core in the centre of a solenoid?
The iron core becomes an induced magnet
This increases the strength of the magnetic field produced
This increases the strength of the magnetic field produced