Year 11 maths · D.1 · Science Calculations: Circuits and Chemistry
Ohm's law
V = I × R.
See worked examples
A 12 Ω resistor is connected to 72 V. What current flows, in amperes?
Answer: 6 A
A current of 6 A flows through a 9 Ω resistor. What is the voltage across it, in volts?
Answer: 54 V
16 V across a resistor drives a current of 2 A. What is its resistance, in ohms?
Answer: 8 Ω
Tip: V = I × R.
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