The Gap Between the Valence and Conduction Bands of a Certain

question 20

Multiple Choice

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 *10^-6 m
• B) is in a range below 1.5 *10^-6 m
• C) is always 1.5* 10^-6 m
• D) is in a range centered on 1.5 *10^-6 m
• E) has nothing to do with the gap

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