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

question 7

Multiple Choice

Light-emitting diodes contain semiconductors that emit light when a current is passed through them.What is the key factor in determining 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:

Eschar

A slough or piece of dead tissue that is cast off from the surface of the skin, particularly after a burn injury.

Pressure Ulcer

A localized injury to the skin and/or underlying tissue, usually over a bony prominence, as a result of pressure, or pressure in combination with shear.

Coccyx

The small, triangular bone at the base of the spinal column, commonly referred to as the tailbone, which can be a source of pain if injured.

Serosanguineous

Pertaining to a fluid that is a mixture of serum and blood, typically seen in wounds as a type of discharge.