What is the Potential Power Output of a Waterfall?

AI Thread Summary
The discussion focuses on calculating the potential power output of a waterfall with a height of 60 meters and a water flow rate of 2000 kg every 5 seconds. Initially, the user incorrectly calculated the velocity and kinetic energy, leading to a power output of 28,800 watts. However, the correct method involves using the formula for gravitational potential energy, resulting in a power output of 235,440 watts. The mistake was clarified as misunderstanding the time duration for the mass flow rate. Accurate calculations are essential for determining the potential power output of the waterfall.
pinnacleprouk
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I don't think I have done it right!

Thanks In Advance!

Homework Statement



Water flows over a 60-m high waterfall at a rate of 2000kg every 5 seconds.
What is the potential power output of the water fall?



Homework Equations



KE = 1/2 mV*2

V = Displacement/time

P = E/t



The Attempt at a Solution



To find out velocity using V = x/t got 12m/s

Using KE = 1/2 mV*2 1/2 x 2000 x 12*2 = 144000J

Using P = E/t 144000/5 = 28800W
 
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No worries I have figured it out

400 kg/s falls 60 m
Energy = mgh = 400 x 9.81 x 60 = 235440 J/s = 235440 W = Power

Thanks
 
Do you understand your mistake in your first attempt? The time you are given is not the time the motion of 2000kg lasts.
 
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