Exit to G3 Physics and O-Level D.C. Circuits Hub

Practical Electric Circuitry Lab

Train circuit build-and-repair logic, correct meter placement, rheostat use, and reading-table workflow for O Level practical questions.

  • SEC G3 Physics 2027
Learning goals
  • Recognise and interpret circuit symbols for cells, batteries, switches, lamps, LEDs, resistors, fuses, ammeters and voltmeters
  • Draw circuit diagrams with cells, batteries, switches, lamps, LEDs, fixed and variable resistors, fuses, ammeters and voltmeters
  • Recognise and interpret circuit symbols for d.c. and a.c. supplies, potentiometers, bells, light-dependent resistors and thermistors
  • Draw circuit diagrams with d.c. and a.c. supplies, potentiometers, bells, light-dependent resistors and thermistors
  • Apply the same-current rule in series circuits

Interactive stageLive model

Loading the interactive model…The interactive model did not load. Try again reloads this page; the explanation and worked content here are still available.

Change one variable at a time and watch the model respond.

Lab setup

Core mode
Reading controls
More controls
4.0 ohm

Practical checkpoint

What to notice:

Prediction target:

      Practice run

      Choose a mode and checkpoint count when you want scoring.

      Run mode

      Choose your checkpoint count for guided or challenge mode.

      Study lensPlace ammeters and voltmeters correctly for common O Level practical setups.12 min activity

      Try this

      Treat the circuit like a measurement workflow: what are you varying, what are you measuring, and is each meter in the right place?

      Learn to

      • Place ammeters and voltmeters correctly for common O Level practical setups.
      • Use a rheostat as the variable component while keeping the rest of the arrangement sensible.
      • Choose the next useful reading or repair step instead of adding random components.

      Exam transfer

      • Practical setup
      • Circuit measurement

      Governing idea

      Current is measured through a component with an ammeter in series; potential difference is measured across it with a voltmeter in parallel. For an ohmic resistor, V = IR.

      Model boundary

      Leads and contacts are ideal unless a fault is shown. Real meters have non-zero resistance and real supplies can have internal resistance.

      Avoid this trap

      Never place an ammeter directly across a supply. Its low resistance can produce a dangerously large current.

      How to explore

      Build and repair circuit setups, place meters correctly, and collect sensible readings without drifting into graph-shape memorising.

      Predict the outcome, change one variable at a time, then interpret the result. Completion records participation only and does not award mastery.

      About this activity

      Train circuit build-and-repair logic, correct meter placement, rheostat use, and reading-table workflow for O Level practical questions. A text explanation and no-JavaScript route remain available.

      How this activity affects progress
      Course and syllabus information
      Course
      SEC G3 Physics
      Edition
      SEC G3 Physics 2027