Electronics fundamentals
Voltage, current, resistance and components.
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Voltage, current, resistance and components.
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Learn Ohm’s law with formulas, worked examples and practical circuit explanations. Check your answers with a free interactive calculator.
Start learning ↗02 / GUIDELearn how to estimate kWh and electricity cost using watts, hours and the price per kWh, with a worked example.
Start learning ↗03 / GUIDEUnderstand the difference between profit margin and markup with formulas and a worked pricing example.
Start learning ↗04 / GUIDELearn compound interest with a formula, worked example, periodic contributions and the limitations of financial projections.
Start learning ↗With a 100 Ω resistor connected to a 12 V source, what current flows?
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