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A thin wire of length l=50cm and area of...

A thin wire of length `l=50cm` and area of cross-section `S=3xx10^(-4)m^(2)` is heated to `727^(@)C`. How much electri power `P` is needed to maintain the wire at this temperature ? Assume that emmissivity of the wire's surface is `e=0.25`.

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The correct Answer is:
`[4.2 watts]`
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