Q. An LVDT is used to measure displacement. The LVDT feeds a Voltmeter of 0-5 V range through a 250 gain amplifier. For a displacement 0.5 mm the output of LVDT is 2 mV. The sensitivity of instrument is

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Q. Assertion (A): When a wattmeter is used for low impedance loads, the pressure coil is connected across the load.

Reason (R): A wattmeter measures apparent power.

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Q. As per BIS there are 6 accuracy classes of instruments.

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Q. If reference sound pressure P₀ is 2 x 10¯⁵ N/m², a sound pressure of 90 dB is equal to

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Q. Which of the following voltmeters would you use for measuring voltage across 20 kΩ resistance?

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Q. A single phase energy meter has the rating 1200 resolutions/ kWh. If a 500 W electric gadget is used for 4 hours, the energy meter will make

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Q. Assertion (A): De sauty's bridge is suitable only for pure capacitor.

Reason (R): Capacitors are mostly perfect.

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Q. In which of the transformer is the secondary nearly short circuited under normal operating conditions?

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Q. The Lissajous pattern observed on screen of CRO is a straight line inclined at 45° to x axis. If X-plate input is 2 sin ωt, the Y-plate input is

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Q. The angle δ for a mica capacitor is about

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Q. A digital voltmeter has a read out range from 0 to 999 counts. If the full scale reading is 9.999 V, the resolution is

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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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