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Homework Help: Gravitational Pot. Engergy & Electrical Pot Energy

  1. Jan 22, 2012 #1
    1. The problem statement, all variables and given/known data

    Compare and contrast gravitational potential energy and electrical potential energy

    2. Relevant equations

    W=ΔEe (work=Δelectrical energy)

    3. The attempt at a solution
    I know what gravitational potential energy is but I don't quite understand what electrical potential energy is. I can grasp that electrical pot. energy is when you do work on a charged object against an electrical field. But how would you go about calculating ΔEe? Would it be similar to calculating gravitational potential energy where W=Force x Distance?

    Thanks in advance.
     
  2. jcsd
  3. Jan 22, 2012 #2
    One interesting difference, we think of mass as some positive quantity, but electric charge comes in positive and negative quantities, (and color charge comes in 6 quantities). Masses attract, charges may or may not.
     
    Last edited: Jan 22, 2012
  4. Jan 22, 2012 #3
    Not quite what was asked for but similar, gravitational potential energy is always negative,

    U = -GMm/R

    but electrostatic potential energy can be positive or negative,

    V = kQq/R

    Which gives rise to masses attract, charge may or may not.

    (what of color potential energy, if there is such a thing, how might it go).
     
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