Electrical Forces in Simple Harmonic Motion: Finding Frequency and Amplitude

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The discussion centers on a physics problem involving a point mass with charge q moving vertically in a frictionless cylinder, influenced by another charge Q at the bottom. The charge q is released from height H and comes to rest at height h above Q, where it begins to oscillate. The key point is demonstrating that the motion will be simple harmonic if the condition H - kqQ/(mgH) is significantly less than the square root of (kqQ)/(mg). The derived height h is kqQ/(Hmg), and it is confirmed that simple harmonic motion (SHM) occurs when the net force acting on the charge is proportional to its displacement from the equilibrium position, akin to Hooke's Law. The frequency of the oscillation is calculated to be 4 times the cube root of (mg^3)/(4π^4kqQ).
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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)
 
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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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