Q. If φsh is flux of shunt magnet, φse is flux of series magnet, ish is eddy current due to φse, the torque in an induction wattmeter is proportional to

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Q. If Eb is the potential of accelerating anode, the energy of electrons as they emerge from electron gun is proportional to

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Q. The circuit of figure is used to measure the value Rx. Ammeter resistance Ra = 0.1 Ω voltmeter resistance Rv = 5000 Ω. It Rx1 and Rx2, are the measured values of Rx with switch in position 1 and 2, the mean of Rx1, and Rx2, is

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Q. If d1, d2, ..., dn are n individual deviations, the standard deviation is

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Q. In figure the values of Rx and Cx are

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Q. If J is moment of Inertia, D is damping constant, C is spring constant, G is displacement constant and I is current throught the coil of DArsonval galvanometer, the equation of motion is

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Q. A meter with a resistance of 100 Ω and a full scale deflection of current of 1 mA is to be converted into voltmeter of 0 - 5 V range. The multiplier resistance should be

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Q. In a resistance strain gauge, G = 2, stress = 1050 kg/cm², R = 1000 Ω. The value of ΔR will be

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Q. The household energy meter is

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Q. A standard cell of 1.0185 V is used with a slide wire potentiometer. The balance was obtained at 60 cm. When an unknown emf was connected, the balance was obtained at 82 cm. The magnitude of unknown emf is

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Q. A dynamometer wattmeter is connected in ac circuit. The measured power is

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Q. Loss of charge method is suitable for medium resistances.

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Q. In two wattmeter method of 3 phase power measurement, when does one wattmeter read negative

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Q. It is required to measure angular position. Out of the transducers

1.Circular potentiometer
2. LVDT
3. E pick up
4. Synchro

The proper devices are

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Q. To increase Q factor of a coil, the wire should be

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Q. An ammeter of 0-25 A range has a guaranteed accuracy of 1% of full scale reading. The current measured is 5 A. The limiting error is

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Q. The coil of a moving iron instrument has a resistance of 500 Ω and an inductance of 1 H. It reads 250 V when a 250 V dc is applied. If series resistance is 2000 Ω, its reading when fed by 250 V, 50 Hz ac will be

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Q. In 3 phase power measurement by two wattmeter method, the reading of one wattmeter is zero. The power factor of load is

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Q. In a CRO which of the following is not a part of electron gun

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Q. In a ballistic galvanometer, a charge of 100 μC gives a first swing of 25°. The charge required to cause first swing of 50° is

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