Water fountain - what power is expended to get it to a certain height?

Maggie W
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Homework Statement


A fountain shoots a stream of water 10 m up in the air. The base of the stream is 10 cm across. What power is expended to send the water to this height?


Homework Equations


Power = change in work / change in time (Joules / second = Watts)
x - x0 = v0t + 1/2at2
v = v0 + at

The Attempt at a Solution


This question is from chapter 8 (Conservation of Energy) in the extended 3rd edition of "Physics for Engineers and Scientists". The Class is Physics with Calculus I. My professor gave this problem as one of the HW assignments, and we turned in the HW already, but he never goes over any of the questions. Just curious on how to get the answer. This is as far as I could go:
Mass is not given.
Velocity = sq rt of 2gh = 14.007 m/s.
Volume = lwh = 0.1(10)w = w.
Density = m/v = m/w. Density of water = 1000 kg/m3. Mass = dv = 1000w.
Power = [mgh/t] = [1000w(9.81)(10) / t] = [98100w/t].
 
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I got it. The answer is 10851.8 Watts.
 
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