1) The prefix mega applies to: a) 100 b) 1000 c) 1000000 d) 10 2) The SI unit of energy is the: a) ohm b) joule c) watt d) coulomb 3) The SI unit of electrical charge is the: a) ohm b) joule c) watt d) coulomb 4) The volt is a measure of: a) potential difference b) power c) voltage d) coulomb 5) The prefix milli applies to: a) 10-2 b) 10-3 c) 10-4 d) 10-6 6) Rearrange the formula R=ρL/A to find ρ a) ρ=R/LA b) ρ=RA/L c) ρ=RL/A d) ρ=A/RL 7) The resistance of a kettle element which takes 12A from a 230V mains supply is: a) 2.88Ω b) 5.00Ω c) 12.24Ω d) 19.16Ω 8) A 12Ω filament lamp was found to be taking a current of 2A at full brilliance. The voltage across the lamp under these conditions is: a) 6V b) 12V c) 24V d) 48V 9) An electron: a) is negatively charged b) is positively charged c) has no charge d) is balanced 10) Domestic wiring uses what kind of insulating material? a) Mica b) PVC c) Mineral oxide d) Glass 11) Good conductor materials include: a) copper b) PVC c) brass d) wood 12) A good insulator materials: a) has lots of free electrons b) has few free electrons c) may be made of copper d) may be made of plastic 13) Which of the following would be considered a load: a) motor b) lamp c) circuit breaker d) switch 14) If the voltage across a lamp is less than the supply. What causes this? a) current drop b) power drop c) resistance drop d) volt drop 15) What kind of meter is connected in series? a) Volt meter b) Ammeter c) Frequency meter d) Watt meter 16) Which of the following uses steam to generate electricity? a) Oil b) Solar thermal c) Coal d) Nuclear 17) Alternating current is used in the distribution and transmission of electricity because: a) it is cheaper than d.c. b) transformers only work with d.c. c) transformers only work with a.c. d) it is safer than d.c. 18) A domestic setting is associated with: a) 400V three phase and neutral b) 400V single phase c) 230V single phase d) 230V three phase and neutral 19) Transmission of electricity on the National Grid is associated with: a) 230V b) 400V c) 25kV d) 132kV 20) If any given power station fails, the National Grid will: a) fail b) shut down temporarily c) use standby power d) divert power from other sources

Electrical Installation Science

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