Mains electricity, circuits

Question 1

What colour is the earth wire?

Answer 1

Green and yellow stripe

Question 2

What colour is the neutral?

Answer 2

Blue

Question 3

What colour is the live wire?

Answer 3

Brown

Question 4

What do the live and neutral wire do?

Answer 4

Carry the current to and from the circuit.

Question 5

What does the wire do?

Answer 5

A safety mechanism that carries away current if there is a fault in a device with a metal case.

Question 6

How does the fuse work?

Answer 6

The fuse will melt and break the circuit if too much current flows.

Question 7

What is the voltage of the neutral wire?

Answer 7

Around 0

Question 7

Why are the pins in a plug made brass?

Answer 7

Good conductor

Question 8

Why is the plug made of plastic?

Answer 8

Insulating

Question 9

What is the average voltage of a plug?

Answer 9

230V

Question 10

What is the voltage of the live wire?

Answer 10

.Very high positivity
.Very high negative

Question 11

What material is the wire?

Answer 11

Copper

Question 12

Where does the earth wire go on the plug?

Answer 12

The top

Question 13

Where does the neutral wire go on the plug?

Answer 13

Left

Question 14

Where does the live wire go?

Answer 14

Right

Question 15

Why does the earth wire have a voltage of zero?

Answer 15

So the current will through objects to the ground

Question 16

Which way do electric current flow?

Answer 16

From high voltage to low voltage

Question 16

What does RCCB stand for?

Answer 16

Residual current circuit breaker.

Question 17

What does the RCCB do?

Answer 17

Detects the current flowing down the earth wire and trips a switch to cut the current flow.

Question 18

What is quicker RCCB or a fuse at disconnecting electricity?

Answer 18

RCCB

Question 19

What type of circuit is a street lamp?

Answer 19

Parallel

Question 20

What is a series circuit?

Answer 20

.Current is the same
.Voltage is shared

Question 21

What us a parallel circuit?

Answer 21

.Current is shared
.Voltage is the same

Question 22

How are voltmeters connected?

Answer 22

In parallel

Question 23

How are Ammeters connected?

Answer 23

In series

Question 23

What does a voltmeter do to a circuit?

Answer 23

It doesn’t let the current through

Question 23

What is current?

Answer 23

The rate of flow of electric charge

Question 24

What is I?

Answer 24

current

Question 25

What is Q?

Answer 25

The amount of charge that flows

Question 26

What is t?

Answer 26

time

Question 27

What is the current measured in?

Answer 27

Amperes

Question 28

What is the amount of charge messed in?

Answer 28

Coulombs

Question 29

What is time measured in?

Answer 29

Seconds

Question 30

How do you work out current?

Answer 30

I=Q/t

Question 31

What is potential difference

Answer 31

work done per unit of charge

Question 32

What is work done?

Answer 32

Energy transferred

Question 33

What happens when resistance increases?

Answer 33

The less current flows

Question 34

What is V?

Answer 34

Potential difference

Question 35

What is I?

Answer 35

Current

Question 36

What is R?

Answer 36

Resistance

Question 37

What does the resistor look like on a graph?

Answer 37

Straight line through the origin

Question 38

What does a bulb look like on a graph?

Answer 38

Curved line through the origin

Question 39

What happens to the resistance of a bulb as temp increases?

Answer 39

Resistance increases

Question 40

What does a Diode look like on a graph?

Answer 40

0 then rises at 0.7 V

Question 41

What is the resistance in a diode like?

Answer 41

Very high

Question 42

What is a thermistor?

Answer 42

A temperature sensitive resistor

Question 42

What happens to the resistance of a thermistor as the temp increases?

Answer 42

Resistance decreases

Question 43

How can a transformer help efficiency of the national grid?

Answer 43

.Potential difference is increased .current decreases .less energy and power lost in the transmission cables

Question 44

What happens to the potential difference of the resistor when the light intensity decreases?

Answer 44

.Resistance of the LDR increases .the current decreases .the potential difference decreases

Question 45

What is resistance?

Answer 45

A measure of how difficult it is for current to flow

Question 46

What is a LDR?

Answer 46

.light dependant resistor .used to detect light levels