Name: ____________________ Red ID _______________ Grade: _______

Instructions: Closed book, closed notes. Use engineering paper. When you are finished, staple your work in sequence (1 to 4), and return this sheet with your work.

1. (20%) Calculate the energy loss in a hydraulic jump, given the sequent depths y₁ = 0.58 m, and y₂ = 2.688 m.

2. (20%) Calculate the sequent depth of a hydraulic jump when the unit-width discharge is q = 5 m²/s and the initial depth is y = 0.5 m.

3. (20%) A hydraulically wide channel is operating at Froude number F = 0.2. The unit-width discharge is q = 3 m²s^-1. What are two Langrange absolute celerities?

4. (20%) You are observing the rising flood stage of a major river in a study reach AB of length 10 km. At your observation point at the downstream point B, the discharge is 500 m³ s^-1 and the stage is rising at the rate of 5 mm hr^-1. The surface width of the river in the study reach is 180 m. What is your estimate of the present discharge at point A? How could you improve the estimate?

5. (20%) Please answer each question in one clear and concise paragraph:

   • Which open-channel flow wave (kinematic, diffusion, or dynamic) attenuates the most in the subcritical regime? Which wave does not attenuate at all?

   • Under what Froude and Vedernikov numbers (for Chezy friction in hydraulically wide channels) do all wave types travel at the same celerity and do not attenuate?

   • What are three ways in which the Seddon formula can be expressed?

   • What is the kinematic hydraulic diffusivity? What is the dynamic hydraulic diffusivity? Which diffusivity (kinematic or dynamic) is more accurate under high-Froude number flows?