Electrical fundamentals · 7 min
Solve a DC circuit, one step at a time
Work through a series–parallel circuit, check the answer with power, and try two practice problems.
Work through this guideLearn by working it out
A clearer way into your next topic.
Start with an example. Follow the reasoning, try a question on your own, then compare your method with the answer. These lessons are open to everyone.
Single-phase AC circuits · 8 min
Find AC current, phase angle and power
Solve a series RLC example with RMS values, use a phasor triangle, and check real and reactive power.
Work through this guideBalanced three-phase circuits · 8 min
Keep line and phase values straight
Compare star and delta using the same load impedances, calculate total power, and find a common √3 mistake.
Work through this guideElectrical machines: transformers · 7 min
Check a transformer with its turns ratio
Calculate secondary voltage, load current and reflected resistance, then use power balance to catch an inverted ratio.
Work through this guideProgramming fundamentals · 6 min
Trace a loop before you run it
Follow variable values through a Python loop, diagnose a boundary mistake, and check your predictions.
Work through this guideStudy practice · 6 min
Turn a past paper into a revision plan
Use a worked marking log to choose your next study session and check whether you can solve a problem independently.
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