Hi kuruman, thanks for the quick response.
As I understand it so far, I should be using, as stated in the question, the equation for simple harmonic motion, i.e., x(t) = Acos(wt). What do you mean by using Newton's Second Law for this case, though? Harmonic oscillation through the second law...
Homework Statement
Using an electron as a point particle of charge −e inside a positively charged sphere of radius R ≈ 10^(−10) m and total charge +e, find the density ρ(r) of the positive charge for which the electron oscillates harmonically about the center of the sphere assuming that the...