(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

(i)Water flows over a dam at the rate 580kg/s and falls vertically 88m before striking the turbine blades. Calculate the speed of the water just before striking the turbine blades (SOLVED) and (ii) the rate at which mechanical energy is transferred to the turbine blades assuming 55% efficiency.

2. Relevant equations

Ek = 1/2mv^2 Mechanical efficiency = Work out/Work in

3. The attempt at a solution

Answer to part (i) v=sqrt2gh

v = 41.5 m/s

Mechanical efficiency = work out/work in

Work out = Ek1 - Ek2

Work in = Ek1 - Ek2/55%

Ok and I'm pretty much stuck. :(

Thanks in advance for any help guys!

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# Homework Help: Mechanical energy/efficiency problem

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