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The wavelength and intensity of light emitted by a LED depend upon ______. - Physics

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Question

The wavelength and intensity of light emitted by a LED depend upon ______.

Options

  • forward bias and energy gap of the semiconductor.

  • energy gap of the semiconductor and reverse bias.

  • energy gap only.

  • forward bias only.

MCQ
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Solution

The wavelength and intensity of light emitted by a LED depend upon energy gap of the semiconductor and reverse bias.

Explanation:

The wavelength (or colour) of light emitted by an LED depends on the energy gap of the semiconductor material. The intensity of light depends on the forward bias current; a higher forward current produces greater light intensity.

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2019-2020 (March) Delhi Set 2

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