The top surface of the passenger car of a train moving at a velocity of 70 km/h is 2.8 m wide and 8 m long The top surface is absorbing solar radiation at a rate of 200 W/m², and the temperature of the ambient air is- 30°C. Assuming the roof of the car to be perfectly insulated and the radiation heat exchange with the surroundings to be small relative to convection, determine the equilibrium temperature of the top surface of the car. Properties of air at 30°C are: The conductivity k = 0.02588 W /m. °C, The kinematic viscosity v == 1.608 x 10-5 m²/s %3D The Prandtl number: Pr = 0.7282. Air 200 W/m2 30°C

The top surface of the passenger car of a train moving at a velocity of 70 km/h is 2.8 m wide and 8 m long The top surface is absorbing solar radiation at a rate of 200 W/m², and the temperature of the ambient air is- 30°C. Assuming the roof of the car to be perfectly insulated and the radiation heat exchange with the surroundings to be small relative to convection, determine the equilibrium temperature of the top surface of the car. Properties of air at 30°C are: The conductivity k = 0.02588 W /m. °C, The kinematic viscosity v == 1.608 x 10-5 m²/s %3D The Prandtl number: Pr = 0.7282. Air 200 W/m2 30°C

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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The top surface of the passenger car of a train moving at a velocity of 70 km/h is 2.8 m wide and 8 m long. The top surface is absorbing solar radiation at a rate of 200 W/m?, and the temperature of the ambient air is 30°C. Assuming the roof of the car to be perfectly insulated and the radiation heat ex- change with the surroundings to be small relative to convec- tion, determine the equilibrium temperature of the top surface of the car. Answer: 35.1°C 200 W/m2 Air 30°C 70 km/h
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QI/The top surface of the passenger car of a train moving at a velocity of 70 km/h is 2.8 m wide and 8 m long. The top surface is absorbing solar radiation at a rate of 200 W/m2, and the temperature of the ambient air is 30°C. Assuming the roof of the car to be perfectly insulated and the radiation heat exchange with the surroundings to be small relative to convection, determine the equilibrium temperature of the top surface of the car. Ans =35.1 c
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