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GPE and KE

  1. May 17, 2012 #1
    If :

    The total energy of a falling rock = G.P.E. (mass x gravity x height) + K.E. (0.5 x mass velocity^2)

    But if a rock reaches terminal velocity (i.e velocity remains the same) but height keep decreasing, then surely Kinetic energy is remaining constant and Gravitational potential energy is decreasing. Where is the loss of energy going?

    Has the first law of thermo dynamics been broken? or is it simply converted into sound energy and heat energy due to air resistance? HHmmmmmm
  2. jcsd
  3. May 17, 2012 #2


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    Why do you think the space shuttle gets VERY HOT when it goes through the upper atmosphere? What do you think is the extra channel for energy loss?

    First law of thermodynamics can't be broken by something this obvious!

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