Bebang owns a 830-mm-thick concrete brick table top that has anarea of 10,000,000 mm^2 and a 0.750-cm-thick glass plate that hasan area of 20,000 cm^2. Assuming the same temperature differenceacross each, what is the ratio of the rate of heat conduction throughthe plate with respect to the rate of heat conduction through thetable top? Use Table 10.1(given below) for the value of ThermalConductivity k.Table 10.1 Thermat Conductivities of Common SubstancesValues are given for temperatures near o °C.SubstanceThermal Conductivity k (W/m-ODiamond2000Silver420Copper390Gold318Aluminum220Steel ironSteel (stainless)14Ice2.2Glass (average)0.84Concrete brickO.84water0.6Fatty tissue (without blood)0.2Asbestos0.16Plasterboard0.16wood0.08-0.16Snow (dry)0.10Cork0.042Glass wool0.042wool0.04Down feathers0.025Air0.023Polystyrene foam0.010

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Bebang owns a 830-mm-thick concrete brick table top that has an area of 10,000,000 mm^2 and a 0.750-cm-thick glass plate that has an area of 20,000 cm^2. Assuming the same temperature difference across each, what is the ratio of the rate of heat conduction through the plate with respect to the rate of heat conduction through the table top? Use Table 10.1(given below) for the value of Thermal Conductivity k. Table 10.1 Thermal Contuctivities of Common Substances Values are gven for tempperatures nearoc. Thermal Conduetivity k (W/m Substance Diamond 2000 saver 420 Copper Gold Aminum 220

Bebang owns a 830-mm-thick concrete brick table top that has an area of 10,000,000 mm^2 and a 0.750-cm-thick glass plate that has an area of 20,000 cm^2. Assuming the same temperature difference across each, what is the ratio of the rate of heat conduction through the plate with respect to the rate of heat conduction through the table top? Use Table 10.1(given below) for the value of Thermal Conductivity k. Table 10.1 Thermal Contuctivities of Common Substances Values are gven for tempperatures nearoc. Thermal Conduetivity k (W/m Substance Diamond 2000 saver 420 Copper Gold Aminum 220

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter4: Numerical Analysis Of Heat Conduction

Section: Chapter Questions

Problem 4.32P

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