Q. Which of the following instruments is used almost exclusively to measure radio frequency currents?

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Q. The coil of a DArsonval galvanometer has N turns. If flux density is B, current is I and area of coil is A, the deflecting torque is

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Q. Consider the following statements regarding electromagnetic flowmeter

1. AC excitation is used to avoid polarisation of fluid.
2. The meter calibration is changed as viscosity of fluid changes.
3. Stainless steel pipes can be used for measuring the flow of liquid of high conductivity.

Of the above statements

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Q. Pirani gauge is used to measure

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Q. Assertion (A): CRT is the most important component of a CRO.

Reason (R): When an electron beam strikes the screen of CRT, a spot of light is produced.

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Q. A capacitance transducer has two plates each of area 5 mm². The coil gap is 2 mm. Displacement sensitivity due to change in gap length is

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Q. Four capacitors are in parallel. Their values are 36.3 μF, 3.85 μF, 34.002 μF and 850 μF with an uncertainty of digit in the last place. The total capacitance in significant figures is

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Q. In a single phase power factor meter the phase difference between currents in the two pressure coils is

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Q. In an ac coordinate potentiometer, the currents inphase and quadrature potentiometer are adjusted to be

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Q. Both X and Y plates of a CRO are excited by ac signals. The display is an ellipse which makes one rotation in 5 seconds. This means that

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Q. In order to achieve accuracy, the slide wire of a potentiometer should be

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Q. In measuring resistance using voltmeter and ammeter, the resistances of voltmeter and ammeter also affect the accuracy of measurement.

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Q. A permanent magnet moving coil measures

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Q. A CT is used to feed current coils of wattmeter, energy meter, power factor meter and an ammeter. Then

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Q. In measurements using strain gauge, the dummy strain gauge is used to

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Q. In an ac single phase energy meter, the potential coil is put on

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Q. The chemical effect of current is used in

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Q. The switch board instruments

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Q. Radiation pyrometer is used to measure temperature in the range of

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Q. The electromagnets of an induction wattmeter

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