The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is

The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is

(A) 11% (B) 9% (C) 1.1% (D) 3%
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1 Answer

Answer :

The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is 11%

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