← Electronics syllabus

SingaporeElectronics

Basic Circuit Concepts

5 dot points across 5 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How do we represent a real circuit on paper using standard symbols so that anyone can read and build it?

Recognise and draw standard circuit symbols, interpret a circuit diagram, and use the conventions for current direction and meter connection
A focused answer to the O-Level Electronics outcome on circuit diagrams. Standard component symbols, reading a schematic, conventional current, and how ammeters and voltmeters are connected.
7 min answer →

What are current, voltage and resistance, and how do they describe what is happening inside an electronic circuit?

Define current, voltage (potential difference) and resistance, state their units, and explain how they relate in a simple circuit
A focused answer to the O-Level Electronics outcome on current, voltage and resistance. Definitions, units, conventional current, and how the three quantities describe a circuit.
8 min answer →

How fast does a component convert electrical energy, and how do we calculate the power it dissipates and the energy it uses?

Define electrical power and energy, apply the power equations, and calculate energy transferred and the cost of running a device
A focused answer to the O-Level Electronics outcome on electrical power and energy. The three forms of the power equation, energy as power times time, and the cost of running a device.
8 min answer →

How does the current through a resistor depend on the voltage across it, and when does that simple relationship hold?

State and apply Ohm's law, define resistance from it, and recognise ohmic and non-ohmic components from their V-I graphs
A focused answer to the O-Level Electronics outcome on Ohm's law. The V equals IR relationship, calculating resistance, and reading V-I graphs for ohmic and non-ohmic components.
8 min answer →

How do current, voltage and resistance behave differently when components are wired in series compared with in parallel?

Apply the rules for current, voltage and resistance in series and parallel circuits, and calculate combined resistance
A focused answer to the O-Level Electronics outcome on series and parallel circuits. The current, voltage and resistance rules for each, and how to calculate the combined resistance.
9 min answer →