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Suppose the bent part of the frame of th...

Suppose the bent part of the frame of the previous problem has a thermal conductivity of `780s^(-1)m^(-1).^(@)C^(-1)` whereas it is `390Js^(-1)m^(-1).^(@)C^(-1)` for the straight the bent part to the rate of heat flow through the straight part.

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The correct Answer is:
A, B

`(Q/t)_(Bent)=(780xxAxx100)/70`
`(Q/t)_(Straight)=(390xxAxx100)/70`
`((Q/t)_(Bent))/((Q/t)_(Straight))=(780xxAxx100)/70`
`xx60/(390xxAxx100)=12/7`
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HC VERMA-HEAT TRANSFER-EXERCIESE
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