An **ideal voltmeter** measuring a potential difference should have:
AResistance equal to the source
BResistance equal to the load
CZero resistance
DInfinite resistance so it draws no current
Answer & Solution
Correct answer: D. Infinite resistance so it draws no current
An ideal voltmeter draws zero current, so it does not disturb the circuit being measured — this requires infinite internal resistance. A potentiometer acts like an ideal voltmeter at the null point.
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