Q. The coil of a moving coil meter has 100 turns, is 40 mm long and 30 mm wide. The control torque is 240 x 10¯⁶ N-m on full scale. If B = 1 Wb/m², range of meter is

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Q. Consider the following statements: In a differential amplifier using JFET, the differential output offset is due to

1. mismatch between FET parameters
2. difference in values of resistances used in circuit
3. variation in supply voltage.

Of the statements, the correct statements are

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Q. A moving coil instrument has a resistance of 0.5 Ω and a full scale deflection of 0.1 A. To convert it into an ammeter of 0-10 A the shunt resistance should be

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Q. Potentiometer method of dc voltage measurement is more accurate than direct measurement using a voltmeter because

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Q. Assertion (A): A hot wire ammeter has a cramped scale.

Reason (R): The heat is proportional to square of current.

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Q. Which of the following is true about an impulse voltage?

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Q. Which of the following are needed both for protection and metering?

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Q. A digital frequency counter can be converted to DVM by addition of a suitable

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Q. A dynamometer wattmeter is connected in ac circuit. The reading will be

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Q. The speed transducer using a drag cup rotor has the main advantage of

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Q. A voltmeter using thermocouples measures

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Q. Which of the following measurements using a dc potentiometer do not require standardisation of potentiometer?

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Q. Which of the following statement is correct for two wattmeters method of power measurement in 3 phase circuit?

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Q. In a thermocouple temperature transducer, the output voltage is usually measured by

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Q. A moving iron instrument gives correct reading when used at

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Q. Induction wattmeter can be used in

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Q. A meter has a square law scale. For 2 A current the deflection in 90°. For a deflection of 45°, the current is

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Q. Consider the following Statements regarding resistance strain gauge

1. The gauge factor is in the range of 2 to 5.
2. The resistance changes due to change in specific resistance with strain.
3. The resistance increases with increase in temperature.

Of the above statements, which are correct?

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Q. PCM employing 4 bit code is used to send data having frequency range from 0 to 2 kHz. The minimum required bandwidth of carrier channel is

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Q. A sinusoidal ac voltage of amplitude 100 V is applied to a rectifying device which offers 10 Ω resistance in forward direction and infinite resistance in reverse direction. The reading on hot wire ammeter will be

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