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The diagram Fig.12 shown a piece of pure...

The diagram Fig.12 shown a piece of pure semiconductor S in series with a variable resistor R, and a source of constant voltage V. Would you increase or decrease the value of R to keep the reading of ammeter constant, when semi-conductor S is heated? Give reason.

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Value of R should be increased with the increase in temperature of semiconductor as circuit resistance decreases and current tends to increase.
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ALLEN -SEMICONDUCTORS-Part-3(Exercise-4)
  1. The diagram Fig.12 shown a piece of pure semiconductor S in series wit...

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  2. At absolute zero temperature Si acts as ……..

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  3. The energy band gap is maximum in …….

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  4. The part of a transistor which is most heavily doped to produce large ...

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

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

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

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

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  9. When npn transistor is used as an amplifler

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

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

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

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

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

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

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

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

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

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

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

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

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