(2) A rectangular weir (dam) is shown below. We wish to compute the flow rate as a function of the max. height of fluid at the weir (H P). Let h1 = variable fluid height before the weir and h2 = variable fluid height at the weir. (a) With suitable choice of datum plane ("zero height"), upstream of the weir I can say: P1 = (H1 - h1 ) g r = gauge pressure What datum plane am I using? (b) Neglecting viscous losses, what is v2 FOR ANY SINGLE STREAMLINE at height h2 as a function of v1 of the same streamline at h1, and other appropriate variables. Note that I can say that P2 ~ 0 (all fluid going over the weir is ~ in contact with air). Assume turbulent flow everywhere. (c) Usually v1 can be neglected in this weir formula. Why? (d) If we want to use the weir as a flow measurement device, what is the integral equation for Q, setting v1 = 0? L = width of the dam. Put in the limits of integration. (e) Integrate and find Q (gpm) for water flowing at ambient conditions per ft of length L, for the