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Homework Help: Power and Fluids

  1. Feb 19, 2006 #1
    Hi. I am having a little difficulty finding the power in this question. It is energy divided by time right? Any help would be appreciated:

    Water is pumped steadily out of a flooded basement at a speed of 5.0 m/s through a uniform hose of radius 1.0 cm. The hose passes out a window 3.0 m above the water line. How much power is supplied by the pump?

  2. jcsd
  3. Feb 20, 2006 #2
    how much water is pumped out per second? You have the radius of the hose and the speed at which is being pumped. Can you fi9nd the quantity pumped per second. (hint: think Volume of water)

    now that you have the volume of water, you can find its mass (density = mass/volume). Remember to be careful of the units here. Once you have the mass, you can find the work done by the motor to raise that mass per second by a height of 3 m. SIne you answer is now J/s you get your answer is Watts (watts=joules/sec) which is what you need.
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