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Homework Help: How much power?

  1. Aug 5, 2014 #1
    For example, if it takes 60 watts of Power for a machine to fly, yet loses (for instance) 2.5 * 10^3 Joules of its energy because of the air resistance, whats the amount of "Power" that was really given in the first place?

    The time of flight for the machine is 30 minutes to get to the height of 2230 meters.

    Any suggestions or tips? I've been stumped by this problem for a while now.

    Last edited: Aug 5, 2014
  2. jcsd
  3. Aug 5, 2014 #2
    It seems that the power is still going to be 60 watts -- even though energy is being lost to air resistance, the engine of the machine is still going to be putting out that much power. So when it flies to a height of 2230 meters, it loses 2.5 * 103 J to air resistance, while also gaining potential energy. Both of these energies will be supplied by the power source.
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