when the DC current flows through the capacitor .the leakage of the charges is in capacitor called Dc leakage capacitor .

The reactance of a capacitor is a function of

-- the capacitance of the capacitor

-- the frequency of the voltage across the capacitor

You can not by-pass the capacitor in an electric motor. Most are capacitor-start motors which require the capacitor to be operational in order to start. If the capacitor is not working then it will need to be replaced.

GANG capacitor is called so because it group of capacitor

when a capacitor is connected to earth

the potential of capacitor becomes zero.

as a result all the charge residing on the conductors of a capacitor passes away and the final charge on capacitor becomes zero