The Cylindrical Filament in a Light Bulb Has a Diameter $3000 ^ { \circ } \mathrm { C } \text {. }$

question 71

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 $3000 ^ { \circ } \mathrm { C } \text {. }$ How long should the filament be in order to radiate 60 W of power? $( \sigma =$ $\left. 5.67 \times 10 ^ { - 8 } \mathrm {~W} / \mathrm { m } ^ { 2 } \cdot \mathrm { K } ^ { 4 } \right)$

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

---

Definitions:

Income Distribution

The way in which total income is shared amongst the members of a society, often analyzed to understand the extent of economic inequality.

Before-Tax Income

The total income earned by an individual or corporation before taxes have been deducted.

Welfare Reforms

Changes or amendments to a country’s welfare policy aimed at improving the effectiveness and efficiency of its social security and aid programs.

Welfare Benefits

Financial assistance or services provided by the government to support individuals or families, especially those in financial need.