Exam-style question
Try this first
A wire has a resistance of 5 Ω and carries a current of 2 A. Calculate the potential difference across the wire.
Model answer
What a good answer should say
- The potential difference across the wire is 10 V.
Explanation
Why this works
The correct answer is The potential difference across the wire is 10 V.. This is correct because it applies the Current electricity idea named in the question, using the required quantities and units rather than mixing current, charge, potential difference, resistance, power, or energy.
The other options are less suitable because they use the wrong electrical quantity, an incompatible unit, or a rule from a different circuit context.
Common mistake
No common mistake is linked to this question yet.