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An electric heater is used in a room of total wall area `137m^(2)` to maintain a temperature of `+20^(@)C` inside it when the outside temperature is `-10^(@)C`. The walls have three different layers materials . The innermost layer is of wood of thickness 2.5 cm, in the middle layer is od cement of thickness 1.0 cm and the outermost layer is of brick of thickness 25.0 cm. find the power of the electric heater. Assume that there is no heat loss through the floor and the ceiling. The thermal conductives of wood, cement and brick are `0.125, 1.5 and 1.0 watt//m// .^(@)C` respectively.

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An electric heatet is uesd in a room of total wall area 137m^(2) to maintain a temperature of 20^(@)C inside it, when the outside temperature is -10^(@)C .The wall have three different layers of matwerials. The innermost layer is of wood of thickness 2.5cm, the middle layer is of cement of thickness 1.0cm and the outermost layer is of brick of thickness 25.0cm. Find the power of the electric heater. Assume that there is no heat loss through the flooor and the celling. The thrermal conductivities of wood, cement and brick aree 0.125Wm^(-1) ^(@)C^(-1) , 1.5Wm^(-1) ^(@)C^(-1) . and 1.0Wm^(-1) ^(@)C^(-1) respectively.

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A electric heater is placed inside a room of total wall area 137m^(2) and maintained at a temperature 20^(@)C inside, outside temperature -10^(@)C . The walls are made up of three composite materials. The innermost layer is made up of wood of thickness 2.5 cm, the middle layer is of cement of thickness 1 cm and the exterior layer is 25 cm thick. Assuming there is no loss of heat through any other way, the power of the electric heater is (the thermal conductivity of wood, cement and brick are "0.125 W m"^(2)""^(@)C^(-1),1.5Wm^(-2)""^(@)C^(-1) and 1Wm^(-2)""^(@)C^(-1) respectively)

An electric heater is used to maintain a temperature of 15^@C inside a room of total wall area 125 m". The outside temperature is -10^@C . The walls of the room are made of three different layers, innermost layer is made of wood of thickness 2 cm, middle layer is made of brick of thickness 20 cm and outermost layer is made of cement of thickness 2 cm. If there is no loss of heat through the floor and ceiling, find the power of heater. Take, thermal conductivities of wood, brick and cement as 0.125 Wm^(-1) ""^@C^(-1) , 1.0 Wm^(-1) ""^@C^(-1) " and " 1.5 Wm^(-1) ""^@C^(-1) , respectively.

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