Home
Class 12
PHYSICS
In a photo diode the conductivity increa...

In a photo diode the conductivity increases when the material is exposed to light. It is found that the conductivity changes only if the wavelength of incident light is less than 500 nm. What is the band gap? Use `h=6.6xx10^(-34)Js, c=3xx10^(8) ms^(-1)`.

Text Solution

Verified by Experts

`E_(g)=(hc)/lambda=((6.6xx10^(-34))xx(3xx10^(8)))/(500xx10^(-9)xx1.6xx10^(-19))eV`
`2*475 eV=2*48 eV`
Promotional Banner

Topper's Solved these Questions

  • ELECTRONIC DEVICES

    PRADEEP|Exercise LONG QUESTION ANSWER|2 Videos

  • ELECTRONIC DEVICES

    PRADEEP|Exercise PROBLEMS FOR PRACTICE|7 Videos

  • ELECTRONIC DEVICES

    PRADEEP|Exercise HIGHER ORDER THINKING SKILLS|1 Videos

  • ELECTROMAGNETIC WAVES

    PRADEEP|Exercise II Focus multiple choice question|5 Videos

  • ELECTROSTATICS

    PRADEEP|Exercise ASSERTION-REASON TYPE QUESTIONS|2 Videos

Similar Questions

Explore conceptually related problems

In a photodiode,the conductivity increases when the material is exposed to light.It is found that the conductivity changes only if the wavelength is less than 620nm.What is the band gap?

In a photodiode the coductivity increases when the material is exposed to light. It is found that coductivity change only if the wavelength is less than 600nm . What is the band gap?

When light falls on a photo diode, its conductivity increases. Experimetally it is found that the conductivity changes only when the wavelength of the incident light is less than 620 nm. The band gap of the diode is

A Photon of red light having wavelength 600 nm has energy equal of (h=6.6xx10^(-34)Js) :

When light of wavelength 400nm is incident on the cathode of photocell, the stopping potential recorded is 6V. If the wavelength of the incident light is to 600nm, calculate the new stopping potential. [Given h=6.6xx10^(-34) Js, c=3xx10^(8)m//s , e=1.6xx10^(-19)C ]

A p-type semiconductor has acceptor energy level 53meV above the valence band. Find the maximum wavelength of light that can creat a hole. Use h=6.63xx10^(-34)Js, c=3xx10^(8)ms^(-1) .

A doped semiconductor has impurity levels 20 meV below the conduction band. Is the material n-type or p-type? What is the wavelength of light so that the electron of impurity level is just able to jump into conduction band? Use h=6.63xx10^(-34)Js, c=3xx10^(8)m//s .

PRADEEP-ELECTRONIC DEVICES-Exercise
  1. The applied input a.c. to a half wave rectifier is 120 watt. The d.c. ...

    Text Solution

    |

  2. Find the average value of d.c. voltage that can be obtained from the h...

    Text Solution

    |

  3. In a photo diode the conductivity increases when the material is expos...

    Text Solution

    |

  4. In a silicon transistor, a change of 8.0 mA in the emitter current pro...

    Text Solution

    |

  5. The current gain for common emitter amplifier is 69. If the emitter cu...

    Text Solution

    |

  6. The potential difference across the collector of a transistor, used in...

    Text Solution

    |

  7. Output characteristics of an n-p-n transistor in CE configuration is s...

    Text Solution

    |

  8. The base current of a transistor is 105 muA and collector current is 2...

    Text Solution

    |

  9. In a silicon transistor, base current is changed by 20muA. This result...

    Text Solution

    |

  10. The input resistance of a silicon transistor is 665Omega. Its base cur...

    Text Solution

    |

  11. A transistor, connected in common emitter configuration, has input res...

    Text Solution

    |

  12. A change of 0.2mA in the base current cause a change of 5mA in the col...

    Text Solution

    |

  13. A transistor is used in common-emitter mode in an amplifier circuit. I...

    Text Solution

    |

  14. For a common emitter transistor amplifier, the audio signal voltage ac...

    Text Solution

    |

  15. A full wave rectifier uses two diodes, the internal resistance of each...

    Text Solution

    |

  16. An a.c. supply if 230V is applied to a half wave rectifier circuit thr...

    Text Solution

    |

  17. A half wave rectifier is used to supply 50V d.c. to a resistance load ...

    Text Solution

    |

  18. In a common emitter transistor amplifier, the input resistance of a tr...

    Text Solution

    |

  19. A transistor is connected in common emitter configuration. The collect...

    Text Solution

    |

  20. In a full wave junction diode rectifier, the input a.c. has r.m.s. val...

    Text Solution

    |