GCSE Electricity

Front

Potential difference

Back

the potential energy per unit of charge.

Front

A lamp is connected to a 24 V power supply. The current through the lamp is 1.5 A. Calculate the power of the lamp.

Back

36 W

Front

What does it mean when it's said that LED lamps are much more efficient than filament lamps?

Back

LED lamps waste a smaller proportion of the input energy than filament lamps.

Front

The diagram shows a temperature sensing circuit used to control a heating system in a house.

What quantity does the ammeter measure? (One correct word only needed)

Back

Current

Front

The diagram shows a temperature sensing circuit used to control a heating system in a house.

The current in the circuit is 3.5 mA when the potential difference across the thermistor is 4.2 V

Calculate the resistance of the thermistor in Ohms (Answer to 2 sig fig, no units needed)

Back

1200

Front

Calculate the potential difference across a 45 Ω resistor with a current of 0.10 A.

Back

4.5

Front

Why is component M included in the circuit?

Back

To vary the current.

Front

An example of an insulator of electricity is...

Back

Rubber

Front

Which switch or switches must be closed to make the lamps light? Options: Only switch 1, Only switch 1, Switches 1 and 2, Switches 1, 2 and 3

Back

Switches 1, 2 and 3

Front

If lamp 2 is unscrewed from its holder, what will happen to lamp1?

Back

It will stay lit