Q. It is required to study transients during switching process. Which CRO should be preferred?

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Q. Assertion (A): In loss of charge method, it is preferable to use an electronic voltmeter.

Reason (R): The resistance of electronic voltmeter is very high.

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Q. If the secondary winding of CT is opened when primary coil is carrying current

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Q. The percentage limiting error in an instrument reading 8.3 V and having guaranteed accuracy of 1% of the full scale reading and range of 0-150 V is

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Q. Consider the following features of an instrument

I. suitable for both ac and dc
II. free from hysteresis and eddy current errors
III. No waveform and frequency errors
IV. it is essentially a voltmeter

This instrument is

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Q. Which one of the following effects is used in measuring power?

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Q. The effect of lead resistance is important in measurement of

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Q. A high resistance was measured by loss of charge method. The voltmeter resistance was 10¹ᴼ ohms. The calculation gave the value of unknown resistance as 0.8 x 10⁹ ohms. The true value of resistance is

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Q. A resistance wire strain gauge has gauge factor 2. If stress is 100 mega newton/m² and Young's modulus is 200 giga newton/ m², the percentage change in gauge resistance due to stress is

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Q. The loss of charge method can be used to measure

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Q. Assertion (A): Maxwell bridge is for measuring inductance of medium magnitude.

Reason (R): In Maxwell's bridge the unknown inductance is measured by comparing it with a capacitance.

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Q. Assertion (A): A semiconductor strain gauge is more accurate than a resistance strain gauge.

Reason (R): The gauge factor of a semiconductor strain gauge is about 100 where as the gauge factor of a resistance strain gauge is only about 2.

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Q. Current density has the dimensions

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Q. The resistance of a dc galvanometer is 20 Ω. A current of 10 mA causes full scale deflection. To convert it into 0-300 V voltmeter, we have to use a series resistance of

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Q. The current in a circuit is measured using a 150 : 1 CT If the ammeter reads 0.6 A, the circuit current is

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Q. A volt ratio box should have low resistance.

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Q. A Hall effect transducer has KH = - 1 x 10¯⁸. If B = 1 Wb/m², I = 3 A and bismuth slab is 2 mm wide, the Hall voltage is

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Q. Two ammeters A and B both 0-10 A have internal resistance of 1 Ω and 0.5 Ω respectively. They are connected in parallel. If total current is 15 A, then

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Q. Which of the following is not correct?

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Q. Assertion (A): Thermocouple instruments can be used for ac only.

Reason (R): Thermocouple instrument has a non linear scale.

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