Q. Consider the following statements as regards induction and dynamometer wattmeters

1. Dynamometer wattmeters can be used for dc only.
2. Induction wattmeter has higher torque and dynamometer wattmeter.
3. Induction wattmeter is less accurate, has more power consumption and more weight than dynamometer wattmeter.

Which of the above statements are correct?

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Q. A Maxwell's bridge has the unknown inductance in one arm and resistance in the other three arms.

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Q. For a current transformer, the standard secondary rating is

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Q. To avoid the effect of stray magnetic fields in ac bridge we can use

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Q. A resistance strain gauge is usually

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Q. Assertion (A): Secondary instruments require calibration at frequent intervals.

Reason (R): Secondary instruments have many errors.

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Q. In ac bridge measurements, 'Wagner ground' means

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Q. In a platinum RTD, the change in resistance for a temperature rise of 50° C is about

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Q. The gauge factor of a semiconductor strain gauge is about

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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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