Q. In a bipolar junction transistor αdc = 0.98, ICO= 2 μA and 1B = 15 μA. The collector current IC is

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Q. The voltage across the secondary of the transformer in a half wave rectifier with a shunt capacitor filter is 50 volts. The maximum voltage that will occur on the reverse biased diode will be

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Q. As temperature increases the forbidden gap in silicon increases.

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Q. Assertion (A): Germanium is more commonly used than silicon.

Reason (R): Forbidden gap in germanium is less than that in silicon.

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Q. Which of the following devices has substrate?

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Q. Assertion (A): The amount of photoelectric emission depends on the intensity of incident light.

Reason (R): Photo electric emission can occur only if frequency of incident light is less than threshold frequency.

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Q. In degenerate p type semiconductor material, the Fermi level,

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Q. Consider the following statements: The function of oxide layer in an IC device is to

1. mask against diffusion or non implant
2. insulate the surface electrically
3. increase the melting point of silicon
4. produce a chemically stable protective layer

Of these statements:

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Q. An extrinsic semiconductor sample has 6 billion silicon atoms and 3 million pentavalent impurity atoms. The number of electrons and holes is

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Q. In a reverse biased p-n junction, the reverse bias is 4V. The junction capacitance is about

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Q. Photoconductive devices uses

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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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