The bob of simple pendulum is hanging vertically down from a fixed identical bob by means of a string of length l. If both bobs are charged with a charge q each, time period of the pendulum is (ignore the radii of the bobs)

Options

A. `2pi sqrt(1/g + (q^(2)/l^(2)m))`
B. `2pi sqrt(1/g - (q^(2)/l^(2)m))`
C. `2pi sqrt(l/g)`
D. `2pi sqrt(1/g - (q^(2)/l))`

Answer

( c)

Explanation

There is only electroststic repulsion that do not affect the motion of the pendulum.
`:. Time period ,T = 2pi sqrt(l/g)`