The defrost of an automobile function by discharging warm air on the inner surface of windshield. To prevent condensation of water on the inner surface, the temperature of the air and surface convection coefficient must be large enough to maintain a surface termperature Ts, i that is at least as high as the dew point temperature, Ts, i > Tdewp. Consider a windshield of length L=800 mm, and thickness t=6 mm, and driving conditions for which the vehicle moves at velocity of V=162 Km/h in ambient air at -15°C. The average convective heat trasfer coefficient on the outside of the windshield may be determined from the correlation. NuL=0.0295.Re^0.8LPr^1/3

Required:
a. If Tdewp=10 and T[infinity],i=50CC, what is the smallest value for hihi required to prevent condensation the inner surface.
b. Plot the thermal equivalent circuit. write the thermal resistances on the circuit