Brainscape's Knowledge GenomeTM

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


See full index

Physics: Grade 11 > Unit 1: Magnets & Electricity > Flashcards

Unit 1: Magnets & Electricity Flashcards

1
Q

Magnet:

A

An object that produces a magnetic field

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

What materials do magnets attract?

A

Ferromagnetic materials

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

List some ferromagnetic materials:

A

Iron, nickel, cobalt and alloys of them

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

Opposite poles….

A

Attract

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

Like poles….

A

Repel

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

Define ferromagnetic:

A

The ability to be magnetized

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

Magnetic field:

A

The distribution of a magnetic force in the region of a magnet

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

Demagnetizations occurs when:

A

When a magnet is physically disrupted or heated to a very high temp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the small magnets called within magnets:

A

Dipoles

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

What do dipoles do in the material:

A

React with other dipoles

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

The dipoles in a demagnetized material face:

A

Random directions

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

If the dipoles line up in a single direction:

A

Small magnetic domains are created

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

Where do dipoles face in a magnetized material

A

The same direction

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

What do the domains do in a strong magnetic field:

A

They line up forming 1 large magnet

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

What does breaking a magnet in 2 cause?:

A

It causes the domains to remain aligned & 2 new magnets are formed

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

How does demagnetization happen:

A

When u disrupt the alignment of the domains so the dipoles are randomly distributed

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

Soft ferromagnetic:

A

Remains magnetic only in the presence of a magnetic field

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

What does a soft ferromagnetic material have:

A

Low loss and high permeability

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

Why does a soft ferromagnetic material lose magnetism quick?:

A

Bc domains inside can be aligned very easily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What magnets are soft ferromagnetic materials used for?

A

Temporary magnets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Hard ferromagnetic materials:

A

Remains magnetic after the magnetic field has been removed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What do hard ferromagnetic materials do?:

A

They strongly resist demagnetization once magnetized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are hard ferromagnetic materials used for:

A

Permanent magnets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Oersteds principle is by:

A

Hand Christine oersted conducted 1820

25
Oersteds principle says:
Electricity moving through a conductor produces a circular magnetic field around the conductor
26
Electromagnetism:
A combo of 2 words - electricity and magnet
27
What affects the field strength:
Number of coils & permeable core
28
Which way does a conventional current flow?
(+) to (-)
29
Which way does an electron current flow:
(-) to (+)
30
What is the motor principle: pt 1.
When a I carrying conductor is placed in an (external) B field, the conductor experiences a force perpendicular to itself and the magnet
31
What happens next in the motor principle? pt.2
When electricity is turned on, I flows though a wire. The wire experiences a force causing it to move in a direction perpendicular to the magnetic field
32
Why does the motor principle work?
(Beginning of oersteds principle) therefore when brought near a wife, the magnet either attracts or repels the wife depending on N &S
33
Explanation of motor principle:
2 fields cause the wire to experience force
34
B field produced by current carrying conductor interacts with:
The external magnetic field of the magnet
35
Faradays law:
Moving or changing the strength of a magnetic field near a conductor cause I to flow in the conductor
36
How do the # of coils affect the current?:
- tightness and compacted wires | - more turns --> greater current
37
How does change of motion (greater or smaller) (of the inducing magnetic field) affect current:
Greater rate --> greater induced current
38
How does the strength of the inducing magnetic field affect the current:
Greater magnetic field strength --> greater induced current
39
What are transformers used for:
To change (transform) voltages from 1 value to another. Used to step up or step down voltages
40
Where are transformers used and why:
In primary generations stations so electricity can travel long distances with little energy loss + low current flow
41
Why is it safe to use a transformer:
Transformers convert electricity to your neighborhood and step down to you home to use safely
42
Transformer explanation:
The AC in the P cool produces a changing magnetic field around the coil which induces a current in the S
43
Why is he energy equal in the transformer coils?:
Bc energy cannot be created or destroyed
44
What does moving a magnetic field do?
Causes electrons to move
45
What does changing a magnetic field do?
Generates current
46
1st step of a transformer:
A p & s coil are connected to a core of ferromagnetic material.
47
2nd step of a transformer:
Electricity runs though the p cool which generates a magnetic field (an electromagnet is created)
48
3rd step of a transformer:
The electromagnet alternates back and forth. An electric current is induced near a word due to the b filed back and forth
49
4th step of a transformer:
Electricity is passed from one coil to another (which aren't touching)
50
5th step of a transformer:
Electric field passes through a magnetic field
51
What does he primary coil do?
Generates magnetic field
52
What does a secondary coil do?
Converts magnetic field to current flow
53
Electricity production:
Power plant, turbine, step up transformer, transmission lines, step down transformer, house
54
Benefits of electromagnet:
B field can b changed quickly by controlling the amount of electricity, control of magnetic strength, greater magnet power
55
What is a turbine:
Wind turns around a 3 propeller blade to a rotor which is connected to the main shaft, which spins + generates electricity.
56
How does a generator work?:
A generator is a device that converts mechanical energy (from an external source) to electrical energy
57
Principle of a generator:
Faradays law
58
Transmission lines:
Sets of wires that Carry electricity from generating plants to a substation that steps the electricity down.

Physics: Grade 11 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions