Transformer Lab for GCSE and A Level Physics

Build step-up and step-down transformers, compare primary and secondary oscilloscope traces, test AC against DC and investigate load, current, power and efficiency.

Learning guide and suggested activities

What this tool shows

How primary and secondary voltage traces follow the transformer turns ratio
Why a transformer changes voltage but not the frequency of an AC supply
How a connected load determines secondary current and useful output power
Why efficiency changes input current, lost power and heating rather than the ideal voltage ratio
Why DC produces switching pulses but no continuous secondary voltage
How polarity dots and probe direction determine the displayed phase relationship

OCR A relevance

OCR A H556 Module 6.3.3(f): ideal transformer relations and transformer investigation techniques
OCR A electromagnetic induction, alternating-current traces and power relationships
OCR GCSE transformer principles are presented as crossover teaching without an invented specification reference

AQA relevance

AQA GCSE Physics 8463 section 4.7.3.4: transformers (Higher Tier)
AQA 7408 section 3.7.5.5: alternating currents and oscilloscope traces
AQA 7408 section 3.7.5.6: transformer ratio, efficiency and losses

Try these tasks

Predict whether the selected windings make a step-up, step-down or isolation transformer.
Calculate the secondary rms voltage before revealing the right-hand trace.
Connect a load and account for input power, useful output power and transformer loss.
Switch from AC to DC, then switch the supply off and on to compare both oscilloscope traces.