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Resistance is measured by the voltmeter ammeter method. The voltmeter reading is 50 V on 100 Volts scale and the ammeter reading is 50 mA on 100 mA scale. If both the meter are guaranteed for accuracy within 2% of full scale, the limit within which resistance is measured will be

Given reading on voltmeter and ammeter is:

V = 50 V I = 50 mA

Resistance R = V/I = 50/50 × 10-3 = 1000 Ω

The limiting error in voltmeter at full scale is ±2% of 100 V = ±2 V. At a reading of 50 V, the error will be 2/50 x 100% = 4%.

The limiting error in ammeter at full scale is ±2% of 100 mA = ±2 mA. At a reading of 50 mA, the error will be 2/50 x 100% = 4%.

Therefore, the total limiting error is 4% + 4% = 8%.

The value of the limiting error in resistance is 8% of 1000 Ω, which is 80 Ω.

Therefore, the limit within which resistance is measured is 1000 Ω ± 80 Ω. Hence, the range of resistance measurement is between 920 Ω and 1080 Ω.