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A piece of copper and another of germani...

A piece of copper and another of germanium are cooled from room temperature to 77 K, the resistance of ……….

A

each of these decreases

B

copper strip increases and that of germanium decreases

C

copper strip decreases and that of germanium increases

D

each of the above increases

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The correct Answer is:
C
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ALLEN -SEMICONDUCTORS-Part-3(Exercise-4)
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  2. The part of a transistor which is most heavily doped to produce large ...

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  3. A piece of copper and another of germanium are cooled from room temper...

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  4. The difference in the variation of resistance with temperature in a me...

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  5. In the middle of the electron layer of a reverse biased p-n junction, ...

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  6. Consider telecommunication through optical fibres. Which of the follow...

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  7. When npn transistor is used as an amplifler

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  8. For a transistor ampliflier in common emiter configuration for load im...

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  9. A piece of copper and another of germanium are cooled from room temper...

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  10. When p-n junction diode is forward biased ………

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  11. The electrical conductivity of a semiconductor of a semiconductor incr...

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  12. In a common emitter amplifier circuit using a n-p-n transistor, the ph...

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  13. In a full wave rectifier circuit operating from 50 Hz mains frequency...

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  14. In a common base mode of a transition , the collector current is 5.48...

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  15. A solid which is transparent to visible light an whose conductivity in...

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  16. Ratio of number density of holes is (7)/(5) and ratio of their current...

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  17. The circuit has two oppsitely ideal diodes in parallel. What is the cu...

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  18. In the following, which one of the diodes is reverse biased ?

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  19. If the lattice constant of this semiconductor is decreased, then which...

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  20. Carbon, silicon and germanium have four valence electrons each. At roo...

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