1. The problem statement, all variables and given/known data Hi Guys, I have this question: b. A model scaled to one-third the size of the prototype has the following characteristics: Omegam = 900 rpm Dm = 5 in deltaHm = 10 ft Qm = 3 ft^3/s Pm = 2 hp If the full-size pump is to run at 300 rpm, what is the power required for this pump? 2. Relevant equations I have found the non dimensional form as: P/rho * omega^3 * D^5 = f(deltaH/D, Q/Omega * D^3) density of the fluid, rho angular speed of the rotor, omega diameter of the rotor, D head rise across the pump, deltaH volumetric flow through the pump, Q 3. The attempt at a solution I'm really not sure where to start, I thought I could equate the model equation, P/rho * omega^3 * D^5 with the real life size version but I don't have enough data to rearrange it and am very confused. Could you guys please offer a hand? The answer is 18. Thanks!