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Homework Help: Frictionless ramp, constant velocity, find work

  1. Oct 29, 2012 #1
    1. The problem statement, all variables and given/known data

    Movers must push a piano onto a truck, the bed of which is a height 1.73 m above the ground. To do this they will use a frictionless ramp. If the piano has a mass of 1635.0 kg and the movers push it up the slope at a constant velocity, how much work do they need to do on it to move it into the bed? Please provide your answer in kilo-Joules (kJ), as the amount of work should be quite large.

    2. Relevant equations

    3. The attempt at a solution
    I have no clue where to start here, no angle?
  2. jcsd
  3. Oct 29, 2012 #2
    Do not think of it as a dynamics problem with forces (i.e. you don't need an angle). This is a conservation of energy problem. The work you put in to the moving the piano up 1.73 m turns in to potential energy. If we think of it in reverse, the potential energy of the piano afterwards is equal to the _______ .

    K + U (before) = K + U (after)

    where K is kinetic energy and U is potential energy.

    K = (1/2)mv2
    U = mgh
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