Q. Insertion of a dielectric material between the plates of an air capacitor

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Q. Two ammeters A and B are connected in parallel in a circuit carrying 100 A. Their resistances are 0.8 mΩ. Their readings will be.

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Q. In household energy meters the flux of series magnet is in phase with current but the flux of shunt magnet lags the voltage by 88°. The reading of energy meters

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Q. Assertion (A): A universal RLC bridge has a battery and also a high frequency ac source.

Reason (R): RLC bridge uses a Wienbridge arrangement for measuring capacitance.

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Q. A capacitance transducer can be used to measure

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Q. The dynamometer principle can be used for

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Q. Assertion (A): In hot wire instrument the material of hot wire in generally platinum iridium.

Reason (R): A hot wire ammeter is suitable for ac only

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Q. The scale of hot wire ammeter is

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Q. A moving coil meter has a shunt of 0.02 Ω resistance. If coil resistance is 1000 Ω and a potential difference of 500 mV is required across it to cause full scale deflection, the current through shunt is

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Q. The emf of a Weston cell is 1.286 V.

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Q. The power factor of a single phase load can be calculated if instruments available are

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Q. A variable reluctance type tachometer has 150 teeth on rotor. The counter records 13500 pulse/sec. The rotational speed is

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Q. The current through the coil of an electromagnet is doubled. The magnetic field around the coil

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Q. In a moving iron voltmeter the coil has a resistance of 20 Ω and an inductance of 0.3 H. The swamping resistance in 2000 Ω. To ensure correct reading with dc as well as 50 Hz ac, the value of capacitor to be connected in parallel with swamping resistance should be

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Q. Two resistances R1 = 18.7 Ω. and R2 = 3.624 Ω in series. The total resistance to the appropriate number of significant figures is

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Q. The input impedance of CRO is about

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Q. Which of the following is not correct in respect of electrostatic instrument?

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Q. The wave applied to X plates, for ohtaining trace of voltage wave, is

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Q. The response of a thermistor overs the whole of its temperatures range is

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Q. A resistance is measured by voltmeter-ammeter method. The voltmeter is 0-250V, ± 1% accuracy and ammeter is 0-5 A, ± 1 % accuracy. The readings of voltmeter and ammeter are 100 V and 2 A respectively. The error in the measured resistance can be

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