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A very small hole in an electric furnace...

A very small hole in an electric furnace is used for heating metals. The hole nearly acts as black body. The area of the hole is `200mm^(2)` To keep a metal at `727^(@)C` heat energy flowing through this hole per sec in joules is `(sigma =5.67 xx 10^(-8)Wm^(-2)K^(-4))` .

A

22.68

B

2.268

C

1.134

D

11.34

Text Solution

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The correct Answer is:
D
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