IGCSEScienceCambridge (CIE)Combined SciencePhysicsExam Questions4. Electricity & MagnetismElectric Circuits & Electrical Safety

Electric Circuits & Electrical Safety (Cambridge (CIE) IGCSE Combined Science: Physics): Exam Questions

Exam code: 0653

12 mins6 questions
1
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1 mark

Two 24Ω resistors are connected in series to a 12 V battery.

Circuit diagram showing a 12 V battery connected in series to two 24 ohm resistors, forming a simple closed loop

What is the current in one of the resistors?

  • 0.25 A

  • 0.50 A

  • 2.0 A

  • 4.0 A

Choose your answer

2
1 mark

The diagram shows a battery that is connected to three LEDs, P, Q and R.

Circuit diagram with a battery and three LEDs labelled P, Q and R; Q and R are in parallel on a branch, with P in series on the main loop.

Which of the LEDs are lit?

  • P only

  • P and Q only

  • Q and R only

  • none of them

Choose your answer

3
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1 mark

The diagram shows a 12 V battery connected to an ammeter and two 10Ω resistors.

Circuit diagram with 12 V battery, ammeter in series, and two 10 Ω resistors connected in parallel between the battery terminals.

What is the reading on the ammeter?

  • 0.60 A

  • 1.2 A

  • 2.4 A

  • 60 A

Choose your answer

4
1 mark

A teacher wants to connect an electric heater to the mains supply.

The safety label on the heater states that the heater is double-insulated.

What does the teacher know from reading this label?

  • The outer casing of the heater does not need to be earthed.

  • The outer casing of the heater must be earthed.

  • The heater needs two fuses.

  • The heater needs two trip switches.

Choose your answer

5
4 marks

Fig. 7.1 shows an electric heater connected in a circuit.

Fig. 7.1

Simple electrical circuit diagram with AC supply, switch, four resistors in series, and a motor labelled M at the bottom marked position X

(i) State the name of component X.

[1]

(ii) The current in component X is 0.5 A.

The current in the heater is 8.3 A.

Circle the value of the current from the source.

0.5 A7.8 A8.3 A8.8 A

[1]

(iii) The electric heater uses 2.0 kW of electrical power.

Electrical energy costs $0.15 per kWh.

Calculate the cost of using the heater for 5.5 hours.

[2]

How did you do?

6
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4 marks

Fig. 9.1 shows a circuit used in a toy car.

Circuit diagram with cell P, switch Q, LED S, fixed resistor R, variable resistor T and motor U connected in series, forming a complete electrical circuit.

Fig. 9.1

(i) The resistance of component T is 5.4Ω. The resistance of component U is 3.5Ω.

Calculate the combined resistance of components T and U.

[1]

(ii) The current in component R is 2.7 A. The current in component T is 2.5 A.

Determine the current in component S and component U.

[2]

(iii) State the name of component S.

[1]

How did you do?