Applied Technology

Question 1

1A 3 kW water heater on 230 V needs a cable rated for at least

Hard

A. 5 A B. 30 A C. 13 A D. 1 A

Question 2

2Electrical appliances with metal cases are earthed so that

Easy

A. they look better B. they use less power C. they work faster D. a fault current flows safely to earth and blows the fuse

Question 3

3A two-way switching circuit allows a light to be controlled

Easy

A. automatically only B. from two different places C. without a switch D. only from one place

Question 4

4Two-way switching is used, for example, to

Easy

A. control a staircase light from both the top and the bottom B. charge two batteries C. run two appliances on one plug D. double the voltage

Question 5

5The consumer unit (distribution board) contains

Easy

A. the TV B. circuit breakers or fuses for each circuit C. the water pipes D. the meter only

Question 6

6A residual current device (RCD) protects people by

Medium

A. raising the voltage B. cooling the cables C. cutting the supply when current leaks to earth D. storing charge

Question 7

7A ring main circuit in a house is used for

Easy

A. the water heater only B. socket outlets C. lighting only D. the doorbell

Question 8

8A residual current device typically trips at an earth leakage of

Hard

A. 30 A B. 3 A C. 30 mA D. 300 A

Question 9

9A miniature circuit breaker (MCB) is preferred to a rewirable fuse because it

Easy

A. never trips B. can be reset after tripping C. is decorative D. uses more copper

Question 10

10Electrical cables in walls are often run in

Easy

A. water pipes B. conduits C. gutters D. curtain rails