A metal block with a heater in it is placed in a room at temperature 293 K. When the heater is switched on it is observed that the temperature of the block rises at the rate of 2^(@)C//sand when its temperature rises to 30^(@)C, it is switched off. Just after when heater is switched off, it is observed that the block cools at 0.2^(@)C//s.If Newton's law of cooling is assumed to be valid, find the power of the heater. Also find the thermal power radiated by the block when it was at 30^(@)C and at 25^(@)C.Given that the heat capacityof the block is 80 J//^(@)C.

A metal block with a heater in it is placed in a room at temperature 2

1.	A metal block with a heater in it is placed in a room at temperature 293 K. When the heater is switched on it is observed that the temperature of the block rises at the rate of 2^(@)C//sand when its temperature rises to 30^(@)C, it is switched off. Just after when heater is switched off, it is observed that the block cools at 0.2^(@)C//s.If Newton's law of cooling is assumed to be valid, find the power of the heater. Also find the thermal power radiated by the block when it was at 30^(@)C and at 25^(@)C.Given that the heat capacityof the block is 80 J//^(@)C.
Answer» ANSWER :`[160 W, 16 w, 8W]`

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