If the metal bob of a simple pendulum is replaced by a wooden bob, then its time period will

The bob of a 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, what is the time period of the pendulum? (Ignore the radii of the bobs.)

$A$ simple pendulum has a time period $T_1$. The point of suspension is now moved upward according to the equation $y = kt^2$,where $k = 1 \ m/s^2$. If the new time period is $T_2$,then the ratio $\frac{T_1^2}{T_2^2}$ will be (take $g = 10 \ m/s^2$):

What is the length of a simple pendulum,which ticks seconds (in $m$)?

$A$ simple pendulum hanging from the ceiling of a stationary lift has a time period $T_1$. When the lift moves downward with constant velocity,the time period is $T_2$,then

$A$ pendulum clock is running slow. In order to correct it, we should: