Electrics

Question 1

What size cables do RCD’s use
(Residual current device)

Answer 1

4mm2

Question 2

How do you work out voltage?

Answer 2

Current times resistance

Question 3

How do you workout current

Answer 3

Voltage divided by resistance

Question 4

How do you workout resistance

Answer 4

Voltage divided by current

Question 5

What is voltage

Answer 5

Pressure of an electromotive force to push round the current

Question 6

What is current

Answer 6

Measures the rate of flow of electrons in a circuit

Question 7

What is resistance

Answer 7

Opposition to current flow like a kink in a pipe

Question 8

Bs 7671

Answer 8

18th edition IET wiring regulations
Document J

Question 9

Maximum voltage drop for lighting circuits

Answer 9

3%

Question 10

Maximum voltage drop for power circuits

Answer 10

5%

Question 11

Where each resistance is follows from another

Answer 11

Series

Question 12

Where each resistance is in line with another

Answer 12

Parallel

Question 13

What level of A or mA can cause Involuntary reactions

Answer 13

15mA 0.015A

Question 14

How many mA on a DC circuit cal cause someone to stick

Answer 14

15-25mA

Question 15

How much will it take to kill you on AC

Answer 15

40mA (0.04A) on a 50Hz supply

Question 16

Ingress protection first number and second number

Answer 16

Finger moisture

Question 17

What to use when measuring current

Answer 17

Ammeter

Question 18

What to use when measuring resistance

Answer 18

Ohmmeter

Question 19

What to use when measuring power

Answer 19

Wattmeter

Question 20

Cross sectional area cables

Answer 20

1mm
1.5mm
2.5mm
4.0mm
6.0mm
10mm

Question 21

Main protective bonding needs to be connected

Answer 21

Witching 600mm ox incoming pipe or writhing 600 of any meter or stopcock and before any tee

Question 22

Supplimentry equipotential binding size

Answer 22

4mm

Question 23

How many volts will overcome someone’s skin

Answer 23

50v AC or 120 DC