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Flashcards in Magnetism Deck (32):
1

all magnets have a ... and a ...

all magnets have a north pole and a south pole

2

the magnetic field flows from ... to ...

the magnetic field flows from the North pole (N) to the South pole (S)

3

what are ferromagnetic materials?

materials that can be magnetised, which are also the ones that are strongly attracted to a magnet
 

4

what are three examples of ferromagnetic materials?

iron, nickel, and cobalt

5

what are permanent magnets?

objects made from magnetised material and produce continual magnetic fields

6

what are three examples non-magnetic materials?

rubber

copper

wood

7

are all substances magnetic?

no

8

what test can you perform to discover whether a substance is magnetic?

get a sample of the substance and hold it against a magnet

if it attracts then it is magnetic

if if does not then it is non-magnetic

9

what do magnets do to other magnets?

repel and attract

10

what do magnets do to magnetic substances?

attract

11

how can the shape of a magnetic field around a bar magnet be revealed? include safety precautions

put paper on cardboard ontop of two wooden blocks

place the magnet undereneath of the cardboard

place a white peice of paper ontop the carbdoard

sprinkle iron filings over the the paper

tap the paper with a pen to reveal the pattern of the magnetic field

safety: wear goggles, don't touch the iron filings, put the experiment into a white tray so you don't spill the iron

12

draw the shape of the magnetic field around a bar magnet

13

what is a magnetic field?

an area around a magnetic material or the moving electric charge through which the force of magnetism acts

14

what are magnetically hard substances?

substances that can be permanently magnetised

difficult to magnetise and demagnetise

these are often alloys of iron, nickel and cobalt

e.g. steel

15

what are magnetically soft substances?

substances that can only be temporarily magnetised - cannot retain their magnetic properties

easy to magnetise and demagnetise

e.g. pure iron

16

what are magnetically hard substances used for?

to make permanent magnets

17

what are magnetically soft substances used for?

to make temporary magnets

18

what test would you perform to discover whether a metal bar is a magnet or not?

it will repel a known magnet

19

you are asked to sort a large pile of empty cans from one another

some are food cans (made of iron)

some are drinks cans (made of aluminium)

how would you go about doing this without looking at the labels?

use a magnet

iron is magnetically soft so it will be attracted to the magnet

aluminium is not attracted to the magnet and will be left in the pile

20

you are presented with three painted metal rods which are identical in appearance except that each is labelled with a letter A,B and C. You are told that one is a piece of soft iron, another is brass and the third is a permanent magnet

what tests would you carry out to decide which bar is which?

hold a magnet to the materials

the brass will not move as it is not magnetic

the iron will attract the magnet

the permanent magnet will repel the magnet

21

what does the term 'magnetic field line' mean?

'lines of force' - lines that show the size and direction of magnetic fields - they always point from North to South magnetic field

22

is magnetism induced in some materials? how?

some materials that are not magnetic can become magneticaly induced when they are close to a magnetic field

after some time they aquire magnetic property

this is because the magnetic field encouraged its electrons to align and form poles

 

23

what does a uniform magnetic field pattern mean?

the field lines are exactly parallel to each other

24

how do you use two permanent magnets to produce a uniform magnetic field pattern?

by keeping the opposite poles face each other

 the region between the poles would establish magnetic field that would be uniform

25

draw the magnetic field lines for two North poles next to each other

26

draw the magnetic field lines for two South poles next to each other

27

which way do the arrows face when drawing magnetic field lines?

north =  going away

south = going in

28

draw the magnetic field lines for one North pole and one South pole facing to each other

attracting

29

define 'magnet'

an object that produces a magnetic field which pulls on other magnetic materials and attracts or repels other objects

30

define 'pole'

either of the two points of a magnet to and from which the lines of magnetic force are directed

31

The closer the magnet and the magnetic material get, the stronger/weaker the induced magnetism will be

The closer the magnet and the magnetic material get, the stronger the induced magnetism will be

32

what is the relationshpi between the distance between the magnetic field lines, magnetic strength and the force?

the closer the magnetic field lines, the stronger the magnetic field strength and the forces