Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Alicja Science - Year 8 > Magnetism > Flashcards

Magnetism Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What 4 metals do magnets pick up?

A

Nickel, cobalt, iron, steel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Name metals that magnets won’t pick up

A

Copper, aluminium, gold, silver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do you show that an object is a magnet?

A

If it is repelled by another magnet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The strongest parts of a magnet are

A

The poles, North and South

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are magnetic materials that are strongly attracted to magnets

A

Ferromagnetic/ nickel, cobalt, iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do you know when a food tin is made of steel?

A

To see if a magnet is attracted to it. Steel is a magnetic material - tin is not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain a fridge door arrangement.

A

The fridge frame and door are both metals that are attracted to the magnetic rubber in between, meaning that they stay shut together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain how to make a magnet using a test tube of iron filings.

A
  • Shake the tube to mix the iron filings
  • Check the tube is not magnetised (both ends attract compass needle)
  • Stroke the tube in 1 direction, with one pole of a magnet. Watch the iron filings line up
  • Check that the tube is magnetised (one end should repel the compass needle)
  • Shake the tube to mix the fillings. Use the compass to check that the magnetism had gone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Does this iron filling experiment suggest that a magnet can be made from magnetic materials?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is a magnet?

A

An object that possess the property of attracting certain substances (iron, nickel, cobalt)
A magnet has two poles called North and South

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is a magnetic material?

A

A magnetic material is a material that can be magnetised and is attracted to magnets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Name another way to magnetise a magnetic material.

A

Place a piece of iron by leaving it next to a magnet for a while. Eventually, the domains move around so they are lined up.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name a few ways on how to remove magnetism

A

Don’t cut it up
• Use a hammer so the vibrations cause the atoms to move around and point in different directions.
• Drop the magnet (for the same reason as above)
• Heat the magnet (excessive heat gives the atoms energy and causes atoms to move rapidly. They knock neighbouring atoms out of alignment)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Domain?

A

A pair of atoms that have a North and South Pole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why doesn’t a normal piece of iron act like a magnet?

A

Because iron is an element that has only one atom. But the domains are not lined up. A material needs to have two to have poles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 3 stages of domains when being magnetised?

A

Unmagnetised, partially magnetised and fully magnetised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why should you NOT drop magnets on the floor?

A

Because the vibrations will mix the domains and the magnet will de magnetise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How can you show a magnetic field using iron fillings?

A
  • Place two exercise books on the table and pit one magnet in the gap between them
  • put a plain sheet of paper over the magnet and rest it on the books
  • Shake the iron fillings onto the paper
  • Tao the corner of the paper with a pencil and keep tapping until you are happy with the pattern

If you want the pattern to be permanent use waxed paper and then melt the wax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How to show a magnetic field using a plotting compass

A
  • Place your magnet in the middle of a sheet of paper - turn the paper so the North end of the magnet is pointing north
  • Draw around the magnet and write an “N” where the North Pole of the magnet is.
  • Then draw a dot at the top right hand corner of the magnet
  • Place the compass there so that the needle points away from the dot
  • Next draw a dot on the paper at the other end of the needle
  • Move the compass to the next dot and do the same for 6 more dots then start at a new position near the magnet
20
Q

What is a magnetic field?

A

The area around a magnet where magnetic materials (eg iron) will experience a force

21
Q

Where will the north needle of a compass point and why?

A

South because opposites attract

22
Q

What materials will let magnetism act through

A

Paper, aluminium, wood etc

23
Q

What happens when magnetism can’t pass trough a material?

A

It will block the magnetic field and the paper clip will drop

24
Q

What are substances that let magnetism act through them

A

Substances that cannot be magnetised.

25
Q

How is a magnetically hard material different from a magnetically soft material?

A

A magnetically hard material retains it’s magnetism

26
Q

Are all metals magnetic materials

A

No, but metals are the only material that can be magnetic materials.

27
Q

Magnetic North is…

A

Geographical South

28
Q

When do compasses not work?

A

When it’s near a magnetic material.

29
Q

What is the best way to increase the strength of an electromagnet?

A

High voltage and current. More amount of coils. Using an iron core

30
Q

What are the dangers that might arise when using an electro-magnet?

A

The core may become extremely hot very quickly

31
Q

What is the difference between a magnet and a magnetic material?

A

Magnetic materials cannot create a magnetic field.

32
Q

Examples of use in magnetism:

A 
Recycling
Navigating- compasses 
Headphones
Computer hard-drives
Fridges
MRI - medical scanners
33
Q

What do you need to make an electromagnet?

A

Power supply
Coil of wire
Soft iron rod
Connecting wires

34
Q

What are the advantages and disadvantages of an electromagnet compared to a bar magnet?

A

You can increase the strength
You can turn it on and off

However an electromagnet needs a constant supply of power

35
Q

Why should soft iron cores be used in electromagnets instead of steel?

A

Because iron can be demagnetised and magnetised quickly whilst steel would stay magnetised after the current is switched off.

36
Q

Thumbs up…

A

Anti-clockwise

37
Q

Thumbs down

A

Clockwise

38
Q

What is an electromagnet?

A

A magnet that runs on electricity. It’s strength can be increased so is a good alternative for a permanent magnet when it comes to moving things.

39
Q

What is conventional current?

A

Current that flows from positive to negative

+ to -

40
Q

What is a long coil called?

A

A solanoid

41
Q

What does a current going through the wire cause…?

A

A magnetic field around the wire

42
Q

3 fingers represent

A

Thumb - M for motion
First finger - F for field
Second finger - C for current

43
Q

Label the parts of a relay circuit for an electric bell

A 
Cell
Switch
Electromagnet 
Gong
Armature
Contacts
Pivot
44
Q

Why do we use Flemings left hand grip rule?

A

To find out the direction of force

45
Q

Order how relay circuits work.

A
  • Switch is turned on
  • Current passes through the coil relay circuit (los current)
  • The magnetic field is produced in the coil
  • The pivoted armature is attracted to the coil
  • The contacts are pushed together
  • The Current passes through the motor circuit (High Current)
  • The starter motor operates to start the car
46
Q

What is a relay circuit?

A

A relay is an electrically operated switch. Many relays use an electromagnet to operate the switch.

47
Q

Electric bells…

A
  • The switch is turned on
  • A magnetic field is produced around the solenoid
  • The armature is attracted to the electromagnet and hits the gong
  • A gap between the contacts breaks the circuit
  • No current can flow so the magnetic field disappears
  • The armature is released back and the contacts touch again
  • The current flows again and the cycle repeats

Alicja Science - Year 8 (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions