3) An advertising sign mounted on the roof of a car is 33 inches tall, 15 inches wide and 54 inches long (airflow direction). The underside of the sign is flush with the top surface of the roof. Take air properties be: p = 0.075 lbm/ft' and u = 1.22x10 Ibm/ft.sec. Used a pressure drag coefficient of 1.2 for the advertisement sign. Calculate the total drag on the sign and the power required to overcome its effect if th car is travelling at a constant speed of a) 12 mph and b) 45 mph.

3) An advertising sign mounted on the roof of a car is 33 inches tall, 15 inches wide and 54 inches long (airflow direction). The underside of the sign is flush with the top surface of the roof. Take air properties be: p = 0.075 lbm/ft' and u = 1.22x10 Ibm/ft.sec. Used a pressure drag coefficient of 1.2 for the advertisement sign. Calculate the total drag on the sign and the power required to overcome its effect if th car is travelling at a constant speed of a) 12 mph and b) 45 mph.

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.49P

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