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An incandesent light bulb has a tungsten...

An incandesent light bulb has a tungsten filament that is heated to a temperature `3 xx 106(3)K` when an electric current passes through it If the surface area of the filament is approximately `10^(-4)m m^(2)` and it has an emissivity of `0.3` the power radiated by the bulb is nearly
`(sigam = 5.67 xx 10^(-8) W m^(-2) K^(-4))` .

A

`138 w`

B

`175 w`

C

`200 w`

D

`225 w`

Text Solution

Verified by Experts

The correct Answer is:
A
`P=eAsigmaT^(4)`
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