Physics-
General
Easy
Question
An incandescent light bulb has a tungsten filament that is heated to a temperature 
when an electric current passes through it. If the surface area of the filament is approximately 
and it has an emissivity of 0.32, the power radiated by the bulb is
- 150 W
- 175 W
- 200 W
- 225 W
The correct answer is: 150 W
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