Electricity Flashcards

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

What is electrical charge measured in

A

Couloms

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

What does 1 Amp of current equal

A

1 Coulomb of charge per second

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

What is the equation of energy transferred by a component

A

E = Q x V

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

What is resistance

A

The potential difference required to drive a current through a component

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

What is resistance measured in

A

Ohms

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

What is a potential difference / Current graph for an ohmic resistor

A

It is directly proportional

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

How does current flow in a diode

A

One direction because a diode has a very high resistance in the reverse direction

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

Why are diodes useful in circuits

A

Controlling the flow of the current

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

When does an LDR have a high resistance

A

Dark conditions

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

What are the uses of LDR

A

Phones and garden lamps

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

What causes the resistance of a thermostat decrease

A

If the temperature increases

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

What is the equation linking energy, power and time

A

Energy =power x time

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

What is power in relation to energy

A

Power is the rate of energy transfer

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

What equation links power, current and resistance

A

Power = current^2 x resistance

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

What type of current is from a cell

A

Direct current

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

What is direct current

A

Current that flows in a single direction

17
Q

What type of current is mains electricity in the UK

A

Alternating current

18
Q

What is alternating current

A

Current that is constantly changing direction

19
Q

What is the advantage of alternating current

A

It is easy to use a transformer which can change the potential difference

20
Q

What is the frequency of alternating current in the UK

A

50 Hz

21
Q

What’s the potential difference of main electricity

A

230 V

22
Q

What metal are the three core cables made of and why

A

Copper as it is a good conductor of electricity

23
Q

What’s the coating of the cable made of and why

A

Plastic as it doesn’t conduct electricity

24
Q

What’s the name of the brown wire

A

Live Wire

25
Q

What is the function of the live wire 

A

It carries the alternating potential difference of 230 V and it is also connected to a fuse in the plug

26
Q

What is the name of the blue wire

A

Neutral wire

27
Q

What is the function of the neutral wire

A

It completes the circuit and has a potential difference of 0 V

28
Q

What’s the green yellow wire called

A

Earth wire

29
Q

What’s the function of the Earth wire

A

It’s the safety wire to stop the appliance from becoming live

30
Q

What happens when someone touches a live wire

A

The current will flow through the body into the Earth causing them to be electrocuted

31
Q

What’s the route from a power station to the Home

A

It goes from the power station to step up transformer to high voltage cables then to step down transformers

32
Q

Why is the energy lost in the power cables

A

The resistance of wires

33
Q

How can energy loss from power cables be reduced

A

Building power stations near to homes