The Tungsten Filament of a Light Bulb Has an Operating

question 50

Multiple Choice

The tungsten filament of a light bulb has an operating temperature of about 2100 K.If the emitting area of the filament is 0.80 cm²,and its emissivity is 0.68,what is the power output of the light bulb? (σ = 5.67 × 10−⁸ W/m² · K⁴)

• A) 100 W
• B) 75 W
• C) 60 W
• D) 40 W

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Definitions:

ATC

Average Total Cost; the sum of all production costs divided by the quantity of output produced, representing the cost per unit.

MC

An abbreviation often used for Marginal Cost, which represents the cost of producing one more unit of a good.

AP

Advanced Placement, a program in the United States and Canada offering college-level curriculum and examinations to high school students.

AVC

Average Variable Cost; the total variable costs divided by the number of units produced, indicating the variable expense per unit of output.