4.3.1

Circuit diagrams and circuit components

Cambridge IGCSE Physics (0625)  · Unit 4: Electricity and magnetism  · 4 flashcards

Circuit diagrams and circuit components is topic 4.3.1 in the Cambridge IGCSE Physics (0625) syllabus , positioned in Unit 4 — Electricity and magnetism , alongside Simple phenomena of magnetism, Electric charge and Electric current.

This topic is examined in Paper 1 (multiple-choice) and Papers 3/4 (theory), plus Paper 5 or Paper 6 (practical / alternative to practical).

The deck below contains 4 flashcards — covering the precise wording mark schemes reward.

What the Cambridge 0625 syllabus says

Official 2026-2028 spec

These are the exact learning objectives Cambridge sets for this topic. Match the command word (Describe, Explain, State, etc.) in your answer to score full marks.

  1. Draw Draw and interpret circuit diagrams containing cells, batteries, power supplies, generators, potential dividers, switches, resistors (fixed and variable), heaters, thermistors (NTC only), light-dependent resistors (LDRs), lamps, motors, bells, ammeters, voltmeters, magnetising coils, transformers, fuses and relays and know how these components behave in the circuit
  2. Draw Draw and interpret circuit diagrams containing diodes and light-emitting diodes (LEDs) and know how these components behave in the circuit Supplement
Key Concept Flip

A circuit contains a 12V battery, a switch, a 10Ω resistor, and an ammeter connected in series. The switch is closed. Calculate the reading on the ammeter.

Answer Flip

Formula: V = IR
Rearrange to find current: I = V/R
I = 12V / 10Ω
I = 1.2A

The ammeter reading will be 1.2 Amperes. Ohm's Law relates voltage, current, and resistance in a circuit.

Key Concept Flip

Describe how the resistance of an NTC thermistor changes as its temperature increases, and state how this change would affect the current in a series circuit containing the thermistor and a fixed resistor powered by a battery.

Answer Flip

As the temperature of an NTC thermistor increases, its resistance decreases.

In a series circuit, if the thermistor's resistance decreases, the total resistance of the circuit decreases. Since the voltage of the battery remains constant, the current in the circuit will increase (due to Ohm's Law: I = V/R).

Key Concept Flip

A circuit contains a 3.0 V battery connected in series with a diode and a 100 Ω resistor. When the diode is forward biased, its forward voltage drop is approximately 0.7 V. Calculate the current flowing through the circuit.

Answer Flip

Current, I = (Voltage of battery - Voltage drop of diode) / Resistance
I = (3.0 V - 0.7 V) / 100 Ω
I = 2.3 V / 100 Ω
I = 0.023 A

Explanation: The current is calculated using Ohm's Law, but first accounting for the voltage drop across the forward-biased diode.

Key Concept Flip

Explain why a diode is often included in a circuit with an LED.

Answer Flip

A diode is often included in a circuit with an LED to protect the LED from reverse voltage and excessive current. Diodes allow current to flow in only one direction. If the voltage polarity is accidentally reversed, the diode will block the current, preventing damage to the LED. They also limit current, increasing LED lifespan.

Review the material

Read revision notes with definitions, equations, and exam tips.

Read Notes

Test yourself

Practice with MCQ questions to check your understanding.

Take Physics Quiz
4.2.5 Electrical energy and electrical power 4.3.2 Series and parallel circuits

More topics in Unit 4 — Electricity and magnetism

Circuit diagrams and circuit components sits alongside these Physics decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.

4.1 Simple phenomena of magnetism

22 flashcards
4.2.1 Electric charge

20 flashcards
4.2.2 Electric current

12 flashcards
4.2.3 Electromotive force and potential difference

14 flashcards
4.2.4 Resistance

10 flashcards
4.2.5 Electrical energy and electrical power

8 flashcards
4.3.2 Series and parallel circuits

24 flashcards
4.3.3 Action and use of circuit components

6 flashcards
4.4 Electrical safety

10 flashcards
4.5.1 Electromagnetic induction

10 flashcards
4.5.2 The a.c. generator

4 flashcards
4.5.3 Magnetic effect of a current

10 flashcards
4.5.4 Force on a current-carrying conductor

6 flashcards
4.5.5 The d.c. motor

4 flashcards
4.5.6 The transformer

16 flashcards

Related Physics guides

Long-read articles that go beyond the deck — cover the whole subject's common mistakes, high-yield content and revision pacing.

IGCSE Physics MCQ mistakes

Single-letter mistakes most often costing marks in Paper 1/2

IGCSE Physics high-yield questions

Equations and reasoning chains that come up every series

IGCSE Physics 2-week revision plan

Daily breakdown for the fortnight before exams

How to study this Circuit diagrams and circuit components deck

Start in Study Mode, attempt each card before flipping, then rate Hard, Okay or Easy. Cards you rate Hard come back within a day; cards you rate Easy push out to weeks. Your progress is saved in your browser, so come back daily for 5–10 minute reviews until every card reads Mastered.