Calculating Liters of Water Raised From Well

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To calculate the liters of water raised from a well by a horse over 8 hours, first convert the well's depth from feet to meters. The work done to raise each liter of water is calculated using the formula W = F * d, where F is the force (mass times gravity) and d is the depth. The energy produced by the horse, assuming it operates at 1 horsepower, translates to approximately 746 watts. By setting up the equation for power and solving for the number of liters raised, the result is about 146.9 liters. The discussion emphasizes the importance of unit conversions and understanding the relationship between work, power, and energy in this context.
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here is the question...water w/ density 1.0 X 10 (3) kg/m cubed, a well 20 feet deep, and a horse worked for 8 hours. How many liters of water did the horse raise from the well? I am ok in unit conversions, but I need help in figuring out steps in solving this problem.
 
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What do you think? How much energy does the horse produce in those 8 hours? (Assume its power is 1 horse power. :wink: And that all its energy goes into raising water.) And how much energy is required to raise a liter of water 20 feet?

(Be sure to convert to standard units--meters, kilograms, watts, joules.)
 
First, the depth of the well was meters, not feet. Second, I'm still not sure if I'm heading in the right direction. If water is 1 kg per liter, the work= F dx, and F= ma...then W= (1kg)(9.8 m/s sq.)(20m) = 196 J for each liter rased from the well. correct? If power is W/ dt, and I let the variable n equal the total number of liters raised, I set up an equation of (196)(n)/ 28800 sec = 1Watt. Solving for n gives me ~146.9 liters. Is this correct?
 
If my memory is correct, for liquids, P = Q * density * height, where Q is flow in volume/unit time.
 
You're still missing the horsepower. How many watts is 1 horsepower?
 
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