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Homework Help: Power / energy question

  1. Nov 23, 2011 #1
    I'm only in high school physics so this may seem easy to you all XD

    1. The problem statement, all variables and given/known data
    The motor for an elevator can produce 14kW of power. The elevator has a mass of 1100kg, including its contents. At what constant speed will the elevator rise?

    2. Relevant equations
    P = E / T?
    Ek = mv^2 / 2

    3. The attempt at a solution

    14000 = E / T
    Ek = 1100v^2 / 2
  2. jcsd
  3. Nov 23, 2011 #2


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    Staff Emeritus
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    Gold Member

    If you use the fact that the power is the rate at which work is done by the motor (P = W/t), and that W = Fd, you can derive a whole new equation for power that consists of only quantities that are mentioned in the problem.
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