The power in a resistor R is estimated by measuring the

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The power in a resistor R is estimated by measuring the voltage and current using the voltmeterammeter method. Two different arrangements can be used as shown in circuits I and II. Less erroneous results are obtained by adopting

1. circuit I for low values of R
2. circuit II for values of R
3. circuit I for values of R
4. circuit II for low and high values of R

Correct Option: A

For low resistance measurements, if circuit II is used, the ammeter resistance which may be comparable with the low resistance being measured gets added to the unknown and thereby causing larger error.