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GaAs (with a band gap = 1.5 eV) as a L.E...

GaAs (with a band gap = 1.5 eV) as a L.E.D can emit

A

blue light

B

green light

C

ultraviolet rays

D

infrared rays

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The correct Answer is:
D
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NEW JOYTHI PUBLICATION-SEMICONDUCTOR ELECTRONICS : MATERIALS , DEVICES AND SIMPLE CIRCUITS -COMPETITIVE EXAM CORNER
  1. When the voltage drop across a p-n junction diode is increased from 0...

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  2. If the voltage between the terminals A and B is 17 V and Zener breakdo...

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  3. GaAs (with a band gap = 1.5 eV) as a L.E.D can emit

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  4. The circuit diagram shows a logic combination with the states of outpu...

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  5. In a common emitter transistor amplifier , the output resistance is 50...

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  6. In the circuit given , the current through the zener diode is

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  7. A transistor oscillator is (i) an amplifier with positive feedback (ii...

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  8. A semiconductor with a band gap of 2.5 eV is used to fabricate a p-n p...

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  9. In the circuit given A , B and C are inputs and Y is the output T...

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  10. In the given circuits for ideal diode , the current through the batter...

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  11. The logic gates giving output '1' for the inputs of '1' and '0' are

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  12. Identify the mismatch of the following :

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  13. If a PN junction diode of depletion layer width W and barrier height ...

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  14. The heavily and lightly doped regions of a bipolar junction transistor...

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  15. The device used for detecting optical signal is

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  16. The logical operation carried out by the above circuit is

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  17. In CE transistor amplifier , if the base current is increased by 20 mu...

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  18. If an ideal junction diode is connected as shown , then the value of t...

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  19. Identify the mismatched pair from the following

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  20. In a common emitter configuration a transistor has beta = 50 and input...

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