The aerodynamic drag of a new sports car is to be predicted at a speed of 50mph at an air temperature of 25 degrees Celcius. Automotive engineers build a one-fifth scale model of the car to test in a wind tunnel. It is winter and the wind tunnel is located in an unheated building. Consequently, the temperature of the wind tunnel air is only about 5 degrees Celcius. During the test, the aerodynamic drag on the model car is measured with a drag balance. Several drag readings are recorded, and the average drag force on the model is 21.2 lb(f).
a) Determine how fast the engineers should run the wind tunnel in order to achieve similarity between the model and the prototype
b) Determine the aerodynamic drag on the full-scale prototyple car