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A room at 20^@C is heated by a heater of...

A room at `20^@C` is heated by a heater of resistence 20 ohm connected to 200 VV mains. The temperature is uniform throughout the room and the heati s transmitted through a glass window of area `1m^2` and thickness 0.2 cm. Calculate the temperature outside. Thermal conductivity of glass is `0.2 cal//mC^@` s and mechanical equivalent of heat is `4.2 J//cal`.

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The correct Answer is:
`[15.24^(@)C`]
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PHYSICS GALAXY - ASHISH ARORA-HEAT TRANSFER -Unsolved Numerical Problems for Preparation of NSEP,INPhO&IPhO
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