What Is the Minimum Horsepower Required to Prevent a Ship from Sinking?

AI Thread Summary
To prevent a leaking ship from sinking, a motor must pump 12.0 units of water per second up 1.50 meters. The initial calculation for work done was correct, yielding 176.4 watts. However, the solution should focus on power, using the formula P = W/t, which accounts for time. The mass of the water must be specified in kilograms for accurate calculations. Clarifying the units of water is essential to ensure the horsepower requirement is correctly determined.
pierra
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Homework Statement



In order to keep a leaking ship from sinking, it is necessary to pump 12.0 of water each second from below deck up a height of 1.50 and over the side.

What is the minimum horsepower motor that can be used to save the ship?

Homework Equations



W=F*d

1 horse power = 746w

The Attempt at a Solution


W=F*d
= mg*d
= (12*9.8)(1.50m)=176.4

176.4w(work) / 746w(horsepower) =0.23646..

p=0.236 hp

I can't see what did I do wrong. help me!
 
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pierra, it looks like you found the Work rather than the power - better to start with a P = formula.
P = W/t = F*d/t would be a terrific start.
Convert the answer to horsepower.
You don't say what units the "12.0 of water" is in and I wonder if that is the trouble with the answer (if it is wrong). You'll need the amount of water in kg to put in for the mass.
 
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