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Electrical forces

  1. Mar 15, 2004 #1
    can anyone help with this?
    a small point mass m carries a charge q. it is constrained to move vertically inside a narrow, frictionless cylinder. at the bottom of the cylinder is another point mass of Charge Q, same sign as q. the charge q is released from a height H and is observed to fall vertically downwards until it comes to rest for the first time at a vertical height h above Q. the charge then oscillates vertically. show that the motion will be simple harmonic if H-kqQ/(mgH) is much less than ((kqQ)/(mg))^.5. and the frequency will equal 4((mg^3)/(4pi^4kqQ)).

    thanks, have been able to show h = kqQ/(Hmg)
  2. jcsd
  3. Mar 15, 2004 #2

    Chi Meson

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    SHM will occur if the net force that pulls an object toward an equilibrium position is directly proportional to the displacement from that equilibrium position (such as Hooke's Law, F=-kx).
    DOes your equation satisfy this requirement?
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