The Cylindrical Filament in a Light Bulb Has a Diameter

question 49

Multiple Choice

The cylindrical filament in a light bulb has a diameter of 0.050 mm,an emissivity of 1.0,and a temperature of 3000°C.How long should the filament be in order to radiate 60 W of power? (σ = 5.67 × 10^-8 W/m² ∙ K⁴)

• A)11 cm
• B)9.4 cm
• C)8.6 cm
• D)7.2 cm
• E)5.9 cm

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Definitions:

Anxiety Disorders

A group of psychological disorders marked by heightened levels of fear, anxiety, and associated behavioral issues.

Bipolar I

A subtype of bipolar disorder characterized by full manic episodes and, in some cases, major depressive episodes.

Manic Episode

A period of abnormally elevated or irritable mood, energy levels, and activity, often associated with bipolar disorder.

Depressive Episode

A period characterized by persistent feelings of sadness, loss of interest, and other emotional and physical symptoms indicative of depression.