A current of 4 A flows through a 10 Ω resistor. What is the potential difference across it?
Answer and explanation
Correct answer: B. 40 V
- Step 1: Ohm's law: .
- Step 2: V.
Answer
40 V.
Why not the others: 2.5 V: it divides resistance by current. 14 V: it adds the numbers. 0.4 V: it divides current by resistance.
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