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A slab of insulating material of thickness 6 cm and thermal conductivity 1.4kJ/m hr deg is placed between and is in contact with two parallel electrodes, and is then subjected to high frequency dielectric heating at a uniform rate of 140,000kJ/m3 hr. At steady state coefficients of combined radiation and convection are 42 and 48 kJ/m2 hr deg. If atmospheric temperature is 25 degree Celsius, find surface temperatures?

A slab of insulating material of thickness 6 cm and thermal conductivity 1.4kJ/m hr deg is placed between and is in contact with two parallel electrodes, and is then subjected to high frequency dielectric heating at a uniform rate of 140,000kJ/m3 hr. At steady state coefficients of combined radiation and convection are 42 and 48 kJ/m2 hr deg. If atmospheric temperature is 25 degree Celsius, find surface temperatures? Correct Answer 121.60 degree Celsius and 115.45 degree Celsius

α = -q g x2 /2k + h 1 α 1/k + α 1. At x =0.06 m and α = α 2, α 2 = -180 + 2.8 α 1. Also q g A δ = h 1 α 1 + h 2 α 2.

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