The Energy Gap Between the Valence and Conduction Bands in a Certain

question 18

Multiple Choice

The energy gap between the valence and conduction bands in a certain semiconductor is 1.25 eV. What is the threshold wavelength for optical absorption in this substance? (c = 3.00 × 10⁸ m/s, 1 eV = 1.60 × 10^-19 J, h = 6.626 × 10^-34 J ∙ s)

• A) 599 nm
• B) 639 nm
• C) 959 nm
• D) 873 nm
• E) 994 nm

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Definitions:

Directional Null Hypothesis

A null hypothesis that specifies the direction of the expected difference or relationship between two variables, which is not a standard form of null hypothesis and might be considered a misinterpretation, as null hypotheses typically state there is no effect or difference.

Directional Alternative Hypothesis

A hypothesis that specifies the direction of an expected difference or relationship, not just the existence of a difference.

Non-directional Alternative Hypothesis

A non-directional alternative hypothesis is a type of hypothesis used in statistical testing that predicts a relationship between variables without specifying the direction of the relationship.

Non-directional Null Hypothesis

A type of null hypothesis that specifies there is no specific direction of difference or relationship between variables.