7J Electricity Summary Sheet

Which of these items is not needed to make a working circuit?

• connecting wires

• a switch

• a component such as a bulb

• a cell

Which instrument would you use to measure current?

• an ammeter

• a cell

• a motor

• a voltmeter

One ammeter in this circuit is reading 3 A. What is the reading on the other ammeter?

• 1 A

• 2 A

• 3 A

• 4 A

A light bulb comes on when a switch is pressed. Which statement is the best explanation for why this happens?

• When you press the switch you make a gap in the circuit.

• When you press a switch you close a gap in the circuit

• The switch is made of metal.

• The switch turns all the bulbs on or off at once

An electric current is:

• a source of energy

• a kind of liquid inside the wires

• tiny particles called electrons flowing through the wires

• tiny particles called volts flowing through the wires

We need to use models to help us to think about electricity because:

• it makes electricity more fun

• electrons are too small to see

• electrons are imaginary

• electricity is not real.

A central heating system can be used as a model for a circuit. Which of these statements is not true?

• The boiler and pump represent the cell

• The pipes represent the wires.

• The radiators represent the bulbs.

• C The radiators represent the bulbs. D The pump represents an ammeter.

Which statement describes a way in which the central heating model is not like an electric circuit?

• The radiator transfers energy to the surroundings.

• Water leaks out of the pipes if you make a gap in the pipes.

• The pump pushes the water through the pipes.

• You can put more radiators into a central heating circuit.

Which of these circuits are parallel circuits?

• X and Y only

• X and Z only

• Y and Z only

• all of them

Which switches must be pressed to make bulb X come on?

• 1 and 2 only

• 1 and 3 only

• 1 and 3 only

• all three of them