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Two Electric bulbs have filaments of len...

Two Electric bulbs have filaments of lengths 1 and 21, diameters 2d and d. The emissivities of the bulbs are 3e, 4e with temperatures in the ratio 2 : 3. Their radiant powers will be in the ratio

A

`4:27`

B

`8:9`

C

`1:8`

D

`2:9`

Text Solution

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The correct Answer is:
A
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