A thin fixed of radius 1 metre has a positive charge `1xx10^-5` coulomb uniformly distributed over it. A particle of mass 0.9 gm and having a negative charge of `1xx10^-6` coulomb is placed on the axis at a distance of 1cm from the centre of the ring. Show that the motion of the negatively charged particle is approaximately simple harmonic. Calculate the time period of oscillations.

Options

A. `0.23s`
B. `0.39s`
C. `0.49s`
D. `0.63s`

Answer

4

Explanation

`E=(1)/(4piepsilon_(0))(qx)/((a^(2)+x^(2))^(3//2))=(qx)/(4piepsilon_(0)a^(3))`
`:. m=(d^(2)x)/(dt^(2))=-(1)/(4piepsilon_(0))(qex)/(a^(3))`
SO motion is `S.H.M`
`omega^(2)=(1)/(4piepsilon_(0))(qe)/(ma^(3))`