4. Under certain conditions, wind blowing past a rectangular speed limit sign can cause the sign to oscillate with a frequency w (see Fig.). Assume that w is a function of the sign width, b; sign height, h; wind velocity, V; air density, p; and an elastic constant, k, for the supporting pole. The constant, k, has dimensions of Nm. (a) Develop a suitable set of pi terms for this problem using b, V, and p as repeating variables. (b) List all the other possible combinations of repeating variables that could have been utilized for this problem. SPEED LIMIT 40

4. Under certain conditions, wind blowing past a rectangular speed limit sign can cause the sign to oscillate with a frequency w (see Fig.). Assume that w is a function of the sign width, b; sign height, h; wind velocity, V; air density, p; and an elastic constant, k, for the supporting pole. The constant, k, has dimensions of Nm. (a) Develop a suitable set of pi terms for this problem using b, V, and p as repeating variables. (b) List all the other possible combinations of repeating variables that could have been utilized for this problem. SPEED LIMIT 40