Elecricity Multiple Choice Questions Set 1

Which component does this circuit symbol represent?

• fuse

• LDR

• thermistor

• variable resistor

What is the equation that links current, potential difference and resistance?

• current = potential difference × resistance

• current = resistance /potential difference

• potential difference = current × resistance

• potential difference = current \ resistance

What is the unit for charge flow?

• amp (A)

• coulomb (C)

• ohm (Ω)

• volt (V)

The potential difference across a motor is 60V and the charge flowing through it is 5C. How much energy is transferred by the motor?

• 12J

• 83J

• 120J

• 300J

Which statement applies to a thermistor?

• the resistance of a thermistor increases as light intensity decreases

• the resistance of a thermistor increases as light intensity increases

• the resistance of a thermistor decreases as temperature decreases

• the resistance of a thermistor decreases as temperature increases

Which component does this graph represent?

• diode

• filament lamp

• LDR

• thermistor

What is the frequency of the UK mains electricity supply?

• 50Hz

• 120Hz

• 230Hz

• 340Hz

What is the equation that links energy, power and time?

• energy= power / time

• energy = power x time

• power = time / energy

• power = energy x time

A filament lamp has a power of 12W and a resistance of 3Ω. What is the current through the lamp?

• 2A

• 3.6A

• 4A

• 16A

What is the National Grid?

• . a dc supply providing energy to homes

• a system of cables and transformers linking power stations to consumers

• a system of underground cables

• a system of parallel circuits inside a home