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Question
The gap between the valence and conduction bands of a certain semiconductor is 0.85eV. When this semiconductor is used to form a light emitting diode, the wavelength of the light emitted:
A) is in a range above 1.5 x10-6m
B) is in a range below 1.5 x10-6m
C) is always 1.5 x10-6m
D) is in a range centered on 1.5 x10-6m
E) has nothing to do with the gap
Answer
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Related questions
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