Light-Emitting Diodes Are Semiconductors That Emit Light When a Current

question 4

Multiple Choice

Light-emitting diodes are semiconductors that emit light when a current is passed through them. What is the key factor that must be changed to change the wavelength of the emitted light in an LED?

• A)the width of the valence band
• B)the width of the conduction band
• C)the width of the band gap
• D)the magnitude of the current
• E)the type of semiconductor (p vs.n)

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Definitions:

Fixed Costs

Costs that remain constant regardless of the amount of goods produced or units sold, including expenses like rent, wages, and insurance premiums.

Short Run

A period in economic analysis where at least one factor of production is fixed, limiting adjustments to changes in demand or supply.

Long Run

A period in economics sufficient for all markets to reach equilibrium, where all inputs and outputs can be varied by firms, not constrained by existing physical capital.