Home
Class 12
PHYSICS
LEDS used for giving infrared radiations...

LEDS used for giving infrared radiations are prepared from

A

silicon dioxide

B

gallium arsenide [Ga As]

C

gallium phosphide [Ga P]

D

gallium arsenide phosphide [Ga As P]

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • ROTATIONAL MOTION

    NIKITA PUBLICATION|Exercise MULTIPLE CHOICE QUESTIONS|405 Videos

  • STATIONARY WAVES

    NIKITA PUBLICATION|Exercise MCQs|396 Videos

Similar Questions

Explore conceptually related problems

Infrared radiation are

Infrared radiation is detected by

Assertion : infrared radiation plays an important role in maintaining the average temperature of earth Reason : Infrared radiations are sometimes referred to as heat waves.

Infrared lamps are used in restaurants to keep the food warm. The infrared radiation is strongly absorbed by water, raising its temperature and that of the food. If the wavelength of infrared radiationis assumed to be 1500 nm, and the number of quanta of infrared radiation produced per second by an infrared lamp (that consumes enregy at the rate of 100 W and is 12% effcient only) is (xx10^(19) , then the value of x is : (Given: h= 6.665xx10^(-34)J-s)

In fog, photographs of the objects taken with infrared radiations are more clear than those obtained during visible light because

Infrared lamps are used in restaurants to keep the food warm. The infrared radiation is strongly absorbed by water, raising is temperature and that of the food. If the wavelength of infrared radiation is assumed to be 1500nm , then the number of photons per second of infrared radiation produced by an infrared lamp that consumes energy at the rate of 100W and is 12% efficient only is y xx 10^(19) . Find the value of y .

If the wavelengths corresponding to ultraviolet, visible and infrared radiations are given as UV, VIS and a IR respectively, then which one of the following gives the correct relationship among these wavelengths?

NIKITA PUBLICATION-SEMICONDUCTORS-MCQS
  1. A solar cell works on the principle of

    Text Solution

    |

  2. The most commonly used semiconducting material used to prepare a solar...

    Text Solution

    |

  3. LEDS used for giving infrared radiations are prepared from

    Text Solution

    |

  4. A light emitting diode is shown as

    Text Solution

    |

  5. A light emitting diode is

    Text Solution

    |

  6. The on/off time or switching time of light emitting diodes is the orde...

    Text Solution

    |

  7. A solar cell is p-n junction operating in

    Text Solution

    |

  8. Barrier potential of Ga-As-P LED is

    Text Solution

    |

  9. V-I characteristics of LED is similar to forward bias characteristics ...

    Text Solution

    |

  10. Which of the following is advantage of LED ?

    Text Solution

    |

  11. Which of the following material is used to produce infrared LED's ?

    Text Solution

    |

  12. The emitter of transistor is doped the heaviest because it

    Text Solution

    |

  13. A transistor is preferable to a triode valve when used in amplifier be...

    Text Solution

    |

  14. The current gain of a transistor is defined as

    Text Solution

    |

  15. Transistors may not replace vacuum tubes in all uses because

    Text Solution

    |

  16. In n-p-n transistor, the p-type crystal acts as

    Text Solution

    |

  17. A transistor is used in the common emitter mode as an amplifier . Then

    Text Solution

    |

  18. Which of the following element is used in making transistors ?

    Text Solution

    |

  19. In transistor symbols, the arrows shows the direction of-

    Text Solution

    |

  20. In an n-p-n transistor, the emitter current is always less than the em...

    Text Solution

    |