To defog the rear window of an automobile, a very thin transparent heating element is attached to the inner surface of the window. A uniform heat flux of 1300 W/m²is provided to the heating element for defogging a rear window with thickness of 5 mm. The interior temperature of the automobile is 22°C and the convection heat transfer coefficient is 15 W/m²·K. The outside ambient temperature is 25°C and the convection heat transfer coefficient is 100 W/m²·K. If the thermal conductivity of the window is 1.2 W/m·K, determine the inner surface temperature of the window.

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Heating element 4, = 1300 W/m? Inside alr, 22°C h, = 15 W/m2K Outside alr, -5°C h.- 100 W/m2-K Rear window k= 1.2 W/m-K L= 5 mm