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GaAs (with a band gap =1.5eV) as an LED ...

GaAs (with a band gap =`1.5eV`) as an LED can emit

A

blue light

B

infrared rays

C

ultraviolet rays

D

`X`-rays

Text Solution

Verified by Experts

The correct Answer is:
B
`lambda=(1242)/(1.5)=828nm`, infrared rays
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CP SINGH-SEMICONDUCTORS-Exercises
  1. A p-n photodiode is fabricate from a semiconductor with a band gap of ...

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  2. A light emitting diode (LED) has a voltage drop of 2V across it and pa...

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  3. GaAs (with a band gap =1.5eV) as an LED can emit

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  4. Zener breakdown in a semi-conductor diode occurs when

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  5. Zener breakdown takes place if

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  6. Zener diode is used as

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  7. A zener diode, having breakdown voltage equal to 15 V is used in a vol...

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  8. If the voltage between the terminals A and B is 17V and zener breakdow...

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  9. Least doped region in a transistor

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

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  11. If l(1),l(2),l(3) are the lengths of the emitter, base and collector o...

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  12. The symbol given in figure represents

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  13. In a transistor base is made thin and doped with little impurity atoms...

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  14. In a normal operation of a transistor, (i) base-emitter junction is ...

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  15. Let I(E),I(C) and I(B) represent the emitter current, the collector cu...

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  16. In NPN transistor the collector current is 10mA. If 90% of electrons e...

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  17. In the study of transistors as an amplifier, if alpha=I(c)//I(c) and b...

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  18. In a transistor, a change of 8.0mA in the emitter current produced a c...

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  19. The current gain of a transistor in a common base arrangement in 0.9...

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  20. In a n-p-n transistor 10^(10) electrons enter the emitter in 10^(-6)s....

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