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Spring-Capacitor Correlation?

  1. Jan 28, 2008 #1
    Hello All,
    I just read in a book that springs are pretty much analogous to capacitors in terms of energy considerations to capacitors.
    For eg.
    If a mass m suspended by a spring comes to rest after downward displacement y,
    Assuming compression = y

    for equilibrium, mg=ky
    thus k = mg/y
    loss in G.P.E for the block =mgy
    gain in elastic P.E of spring = 1/2(ky^2)
    = 1/2(mgy)
    ----->Half energy is wasted
    can't this be compared to charging of capacitor by a battery?
    energy lost by battery = qV
    but energy gained by capacitor =1/2(qV)
    ------> Half energy is wasted

    I have difficulty in solving capacitor probs.
    Does this mean that springs can be used instead of them?
  2. jcsd
  3. Jan 29, 2008 #2
    IMHO, the analogy works better for a heavily damped spring and an RC circuit. I would recommend getting thoroughly familiar with capacitor basics before looking at analogs.
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