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Potential energy of a book resting on a floor

  1. Sep 21, 2005 #1
    What energy a book resting on a floor has? If it rests on a table it will have a potential energy equal to mgh where h is the height of the table,m is the mass of the book and g is the gravity but if it rests on the floor what is the energy it has? Any thoughts on this?
  2. jcsd
  3. Sep 21, 2005 #2
    Whatever you want. I can readjust the "zero" of my potential energy by adding a constant to it without affecting the physical dynamics of any problem.
  4. Sep 21, 2005 #3


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    The work done in raising the book from the floor to the top of the table, at height h, is W = F.d = mg.h. So, we have, from the work-energy theorem : U(floor) + work done = U(table), and plugging in values, U(floor) + mgh = mgh. Hence, U(floor) = 0
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