Brainscape's Knowledge GenomeTM

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


See full index

Physics > Electricity P2 > Flashcards

Electricity P2 Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What type of current do car batteries dry cells and solar cells have?

A

Direct

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

How do power stations sometimes produce electricity? What type of current is this ?

A

Via magnets. Alternating current

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

What does the UK mains electricity supply generate a frequency of?

A

50 hertz (Hz)

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

What does the UK mains electricity supply deliver electricity at ?

A

230Volts (V)

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

What is the function of outer insulation in the plug?

A

All three wires in the cable are bundled together with an extra plastic insulation wrapped around them for safety

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

What does the cable grip do in a plug?

A

It holds the cable tightly in place, so wires don’t come loose

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

What is the function of the live wire within a plug?

A

Is a copper wire with brown plastic along where the current enters the device?

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

What colour is the live wire?

A

Brown

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

What is the function of the fuse?

A

Is a glass or ceramic canister containing a thin wire that melts if the current is too high

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

Function of the neutral wire

A

Is a copper wire coated in blue plastic that connects the cable in the wall to complete the circuit

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

What colour is the neutral wire?

A

Blue

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

What is the function of the earth wire?

A

It is a copper wire coated in green and yellow striped plastic that provides a path for the current to flow from the case of the device to the ground. In the chance there is a fault.

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

What is the colour of the earth wire?

A

Green and yellow (striped)

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

What does 50 Hz actually mean?

A

The current changes direction and back again 50 times/s

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

What does the live wire carry?

A

Alternating potential difference from the electricity supply

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

What is the voltage like in the Earth wire and why?

A

It is at 0 V since it only carries a current if there is a fault

17
Q

What does the Earth wire provide?

A

A low resistance path to the ground

18
Q

What is voltage like in the neutral wire?

A

Pretty close to 0 V

19
Q

What would happen if the live wire was loose and we had no earth wire?

A

The next person to touch the plug would be electrocuted

20
Q

What does the fuse do and why?

A

If there is a fault that causes the casing of device to become live a large current flows through the low resistance earth wire causing the fuse to melt and break the circuit

21
Q

What is the equation that links energy power and time?

A

Energy equals power times time, E= PxT

22
Q

What is the equation linking potential difference power and current?

A

Power= potential difference x current, P=VxI

23
Q

What does the national grid do?

A

Distribute electricity across the country it connects power stations to homes workplaces and buildings. The electricity may be produced by conventional power generator station turning on a generator or another way.

24
Q

What do pylons do?

A

They carry electricity cables high above the ground

25
Q

What is a transformer?

A

A device that changes the potential difference of voltage of an electrical supply in transmission lines

26
Q

What is a step up transformer?

A

Increases the voltage from about 25,000 V to 400,000 V and decreases the current

27
Q

What is a step down transformer?

A

Decreases the voltage and increases the current

28
Q

When is a step up transformer used and why?

A

Before the electrical power leaves a power station it goes for a step up transformer to a volt 400,000 V to save money and energy

29
Q

What happens when electrical power reaches a local area?

A

It goes for a step down transformer to around 230 V for domestic use

30
Q

What is the equation to check if a transformer is 100% efficient?

A

Potential difference across primary coil x current in primary coil = potential difference across secondary coil x current in secondary coil

31
Q

How are the cables adapted to ensure minimum amount of power is lost/ dissipated ?

A

Theyre thick so the resistance is low and they are high voltages used to reduce current through transmission lines

Physics (10 decks)

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