Q. Assertion (A): Oxide coated cathodes are very commonly used.

Reason (R): Work function of oxide coated cathode is 1 eV whereas it is 4.5 eV for pure tungsten.

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Q. An increase in junction temperature of a semiconductor diode

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Q. An air gap provided in the iron core of an inductor prevents

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Q. Generally, the gain of a transistor amplifier falls at high frequency due to the

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Q. Which of these has a layer of intrinsic semiconductor?

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Q. Assertion (A): When Diode used as rectifier the reverse breakdown voltage should not be exceeded.

Reason (R): A high inverse voltage can destroy a p-n junction.

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Q. Assertion (A): The forward resistance of a p-n diode is not constant.

Reason (R): The v-i characteristics of p-n diode is non-linear.

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Q. For a photoengraving the mask used is

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Q. In a varactor diode the increase in width of depletion layer results in

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Q. The work function of a photo surface whose threshold wave length is 1200 A, will be

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Q. Determine the transistor capacitance of a diffused junction varicap diode of a reverse potential of 4.2 V if C(0) = 80 pf and VT = 0.7 V

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Q. At room temperature the barrier potential in a silicon diode is

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Q. The cut in voltage of a diode is nearly equal to

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Q. Assertion (A): In a BJT base current is very small.

Reason (R): In a BJT recombination in base region is high.

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Q. A reverse voltage of 18 V is applied to a semiconductor diode. The voltage across the depletion layer is

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Q. The diameter of an atom is

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Q. N-type silicon is obtained by doping silicon with

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Q. When a p-n junction is reverse biased

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Q. If a sample of germanium and a sample of Si have the impurity density and are kept at room temperature then

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Q. When a large number of atoms are brought together to form a crystal

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