Domestic Uses and Safety

Question 1

alternating current

Answer 1

• PD switches many times a second

- current switches direction

Question 2

direct current

Answer 2

• PD remains in one directions

- current flows in the same direction

Question 3

National Grid

Answer 3

distributes electricity generated in power stations around the UK

Question 4

step-up transformers

Answer 4

• increase voltage, decrease current

- increases efficiency, reduces heat loss

Question 5

step-down transformers

Answer 5

• decrease voltage, increase current

- makes it safer for houses

Question 6

live wire

Answer 6

• brown
• carries PD from mains supply
• PD between live and earth = 230V

Question 7

neutral wire

Answer 7

• completes the circuit

- PD = 0V

Question 8

earth wire

Answer 8

• green and yellow stripes
• only carries a current if there’s a fault
• PD = 0V

Question 9

earthing

Answer 9

• a safety device

- earth wire joins the metal case