Which one of the following statement is not correct in the case of light emitting diodes?
A. It is a heavily doped p-n junction.
B. It emits light only when it is forward biased.
C. It emits light only when it is reverse biased.
D. The energy of the light emitted is equal to or slightly less than the energy gap of the semiconductor used.
Choose the correct answer from the options given below:
Solution
The correct answer is C. It is not correct that a light-emitting diode (LED) emits light only when it is reverse biased. In fact, an LED emits light only when it is forward biased, which is stated correctly in option B.
<br/><br/>Option A is also correct, as an LED is indeed a heavily doped p-n junction. Option D is also correct, as the energy of the light emitted by an LED is equal to or slightly less than the energy gap of the semiconductor material used in the device.
<br/><br/>Therefore, the statement that is not correct in the case of light-emitting diodes is C.
About this question
Subject: Physics · Chapter: Electronic Devices · Topic: p-n Junction Diode
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