P5 Electricity In The Home

Question 1

What is the purpose of step up transformers?

Answer 1

They increase the voltage to several hundred thousand volts to reduce energy loss through the wires, as the voltage is very high

Question 2

What is the National Grid?

Answer 2

The Transformers and the cables

Question 3

Describe 2 ways to decrease energy transfer through wires in the National Grid

Answer 3

• Move homes closer to the power station

- Use transformers

Question 4

What is the purpose of step down transformers?

Answer 4

They reduce the voltage to around 230V so it can be safely passed into homes

Question 5

What type of current is the UK Mains?

Answer 5

Alternating current

Question 6

What voltage and frequency is the UK Mains?

Answer 6

230V at 50Hz

Question 7

What colour is the live wire

Answer 7

Brown

Question 8

What are the coatings of the wires in a plug made of?

Answer 8

Plastic

Question 9

What colour is the neutral wire?

Answer 9

Blue

Question 10

What colour is the earth wire?

Answer 10

Green and yellow striped

Question 11

What is the voltage of the neutral wire compared to the live wire?

Answer 11

0V (Live wire is around 230V)

Question 12

What is the purpose of the neutral wire

Answer 12

It completes the circuit with the live wire

Question 13

What is the purpose of a fuse?

Answer 13

If the current going through it is too great, it breaks, opening the circuit

Question 14

What is the purpose of the earth wire?

Answer 14

If the appliance becomes live, current travels to the earth through the earth wire, and the fuse melts

Question 15

What is meant by a device being very efficient?

Answer 15

Most of its input energy is usefully transferred