The Tungsten Filament of a Light Bulb Has an Operating

question 26

Multiple Choice

The tungsten filament of a light bulb has an operating temperature of about 2 050 K.If the emitting area of the filament is 0.70 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)70.1 W
• B)47.7 W
• C)477 W
• D)42.7 W
• E)39.7 W

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Definitions:

Carpetbagger

A derogatory term originally used to describe Northerners who moved to the South after the American Civil War to profit from the Reconstruction.

Maine

The northeasternmost state in the United States, known for its scenic coastlines, lighthouses, and as a major producer of lobsters.

South

A region in the United States characterized by its unique cultural, historical, and economic attributes, often distinguished by its geographic location below the Mason-Dixon line.

Bargain of 1877

Deal made by a Republican and Democratic special congressional commission to resolve the disputed presidential election of 1876; Republican Rutherford B. Hayes, who had lost the popular vote, was declared the winner in exchange for the withdrawal of federal troops from involvement in politics in the South, marking the end of Reconstruction.