P5 - Electricity In The Home Flashcards

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

What’s an alternating current?

A

An alternating potential difference causes current to periodically reverse its direction.

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

What’s an example of an alternating current (ac)?

A

Mains electricity is an ac supply.

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

What’s a direct current?

A

A direct potential difference causes the current to flow in one direction only.

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

What’s an example of a direct current (dc)?

A

A battery is a dc supply.

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

What colour is the live wire?

A

Brown

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

What’s the function of the live wire?

A

The live wire carries the alternating potential difference from the supply.

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

What’s the potential difference between the live wire and the earth?

A

230V

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

Why is touching the live wire dangerous?

A

•Touching the live wire and making a connection to earth causes a person to be electrocuted.
•This can be fatal, therefore the live wire is dangerous.

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

What colour is the neutral wire?

A

Blue

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

What’s the function of the neutral wire?

A

The neutral wire completes the circuit

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

What’s the potential difference of the neutral wire?

A

0V

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

What colour is the earth wire?

A

Green and yellow stripes

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

What is the function of the earth wire?

A

It only carries current if there is a fault. It is a safety feature.

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

What is the potential difference of the earth wire?

A

0V

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

How is electrical power transferred from power stations to consumers?

A

By using the national grid

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

What is the national grid?

A

A system of cables and transformers linking power stations to consumers

17
Q

What is the purpose of step up transformers?

A

They increase the potential difference in the transmission lines meaning increasing voltage and decreasing current.

18
Q

Why is the current lowered in a step up transformer?

A

Low current means less energy is lost through heating the wire, so is a more efficient way to transfer energy

19
Q

What is the purpose of step down transformers?

A

They decrease the potential difference to a safer voltage for use in homes and increase current