A large, rigid, rectangular billboard is supported by an elastic column as shown in Fig....

A large, rigid, rectangular billboard is supported by an elastic column as shown in Fig. P7.42. There is concern about the deflection, δ, of the top of the structure during a high wind of velocity V. A wind tunnel test is to be conducted with a 1:15- scale model. Assume the pertinent column variables are its length and cross-sectional dimensions and the modulus of elasticity of the material used for the column. The only important “wind” variables are the air density and velocity. (a) Determine the model design conditions and the prediction equation for the deflection. (b) If the same structural materials are used for the model and prototype, and the wind tunnel operates under standard atmospheric conditions, what is the required wind tunnel velocity to match an 80-km/hr wind?