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About 5% of the power of a 100 W light b...

About `5%` of the power of a `100 W` light bulb is converted to visible radiation. What is the average intensity of visible radiation
(a) at a distance of `1 m` from the bulb?
(b) at a distance of `10 m` ?
Assume that the radiation is esmitted isotropically and neglect reflection.

A

`(5) /(2 pi (10)^2)` watt/`m^2`

B

`(5)/(4 pi (10)^2)` watt/`m^2`

C

`(5)/(pi (10)^2)` watt/`m^2`

D

`(5)/(8pi (10)^2)` watt/`m^2`

Text Solution

Verified by Experts

The correct Answer is:
B
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