Brainscape's Knowledge GenomeTM

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


See full index

A Level Physics > Magnetic Fields > Flashcards

Magnetic Fields Flashcards

1
Q

What shape is the B-field of a Bar Magnet?

A

Large loops from North to South

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

What is the shape of the B-field of a Horseshoe Magnet?

A

They are uniform from North to South

Uniform Field

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

How can you find the Direction of the B-field around a Wire?

A

Right Hand Screw Rule
Finger point in direction of B-field
Thumb points in direction of Current

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

What symbols show whether something is moving towards or away from you?

A

Circle with a cross is moving away (imagine the fletching of an arrow)
Circle with a point in is towards (imagine the point of a arrow)

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

How do you know which end of a field is the North or South pole?

A

Stylised N arrow pointing with the current is North

Stylised S arrow pointing with the current is South

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

How do you work out the direction of the field of a Solenoid?

A

Right Hand Screw Rule

But with Fingers the Current and pointing if the Thumb being the B-Field

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

What is Flemming’s Left Hand Rule?

A

Technique to idenitify the direction of the B-Field (first finger), Current (middle finger) and Force (thumb).

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

What happens to two parrallel wires if the have current in the same direction?

A

They are attracted

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

What happens to two parrallel wires if the have current in the opposite direction?

A

They are repeled

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

What is the equationthat links Force, B-Field, Current and length of wire.

A 
F = BIL
F = Force
B = Magnetic Field
I = Current
L = Length of wire within the field
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When is F = BIL applicable?

A

When Current is perpendicular to field lines

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

What is μ0?

A

The Permeability of free space

4π x 10^-7 Hm^-1 (Henry per meter)

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

What is meant by μ0?

A

The measure of the ability to support the formation of a magnetic field in a vaccum

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

What equation links Force, B-Field, Charge, and velocity/direction of motion?

A 
F = BQV
F = Force
B = Magnetic Field
Q = Charge
V = Velocity/Direction of motion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What shape does a Charged Particle move in when within a Uniform B-field?

A

Circular motion

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

What are uses of Changing the direction of particles in a B-field?

A

Cyclotron

Mass Spectrometer

17
Q

What is Electro-Magnetic Induction?

A

When an EMF is produced by moving a a current length through magnetic field lines?

18
Q

When is Felmings Right Hand Rule?

A

The induction equivelant of FLHR
Force is thumb
B-Field is first finger
Velocity or current is middle finger

19
Q

An EMF is induced by?

A

Moving a wire
Moving a magnet
Changing the strength of the magnet
Changing the number of turns in the wire

20
Q

What is Magnetic Flux?

A

The total amgnetic field which passes through an area

21
Q

What is the Equation for Magnetic Flux?

A 
Φ = BA x Cosθ
Φ = Magnetic Flux
B = B-field
A = Area
θ = Angle between normal and plane of the area
22
Q

What is the symbol and units of Magnetic Flux?

A

Symbol: Φ
Units: Wb (Webber) or Vs

23
Q

What is the Equation for Flux Linkage?

A 
NΦ = NBA x Cosθ
NΦ = Flux Linkage
N = Number of turns cutting the flux
B = B-field
A = Area
θ = Angle between the normal and the plane of the area
24
Q

What is the Symbol and Units of Flux Linkage?

A

Symbol: NΦ
Units: Wb turns (Webber turns)

25
Q

What is Faraday’s Law?

A

Magnitude of the induced EMf is equal ro the rate of change of Flux Linkage

26
Q

What is the Equation for Faraday’s law?

A 
ε = NΔBA/Δt
ε = Induced EMF
N =Number of turns
ΔBA = Change in magntic flux as Φ = BA
Δt = Change in time
27
Q

What is Lenz’s Law?

A

The induced current (EMF) is such as to oppose the change which caused the current(EMF)

28
Q

What is the Generator Equation?

A 
ε = (BANω) x Sin(ωt)
ε = Induced EMF
B = B-field
A = Area
N = Number of turns
ω = Radial Velocity
t = period
29
Q

What are examples of Magnetic induction?

A

Electrical Generators
Electro-Magnetic Braking
Jumping Rings

A Level Physics (16 decks)

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