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MHT CET Medical202626 April 2026Morning ShiftPhysicsSemiconductorsActual

Out of the following what is used to detect the intensity of light ?

Options

  1. ALED in forward bias.
  2. BPhotodiode in forward bias.
  3. CLED in reverse bias.
  4. DPhotodiode in reverse bias

Correct answer

D. Photodiode in reverse bias

Step-by-step solution

A photodiode is a p-n junction diode fabricated with a transparent window to allow light to fall on the diode. It is operated under reverse bias. When the photodiode is illuminated with light (photons) with energy greater than the energy gap of the semiconductor, electron-hole pairs are generated due to the absorption of photons. Due to the electric field of the junction, electrons and holes are separated before they recombine. The magnitude of the photocurrent is directly proportional to the intensity of incident

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