What happens if the magnitude of the capacitance of a capacitor is large? Define dielectric breakdown and dielectric strength.

(N/A) If the magnitude of the capacitance $C$ of a capacitor is large,the potential difference $V$ is small for a given charge $Q$,because $C = Q/V$.
This means a capacitor with large capacitance can hold a large amount of charge $Q$ at a relatively small potential difference.
High potential difference implies a strong electric field around the conductors.
$A$ strong electric field can ionize the surrounding air and accelerate the charges so produced to the oppositely charged plates,thereby neutralizing the charge on the capacitor plates at least partly.
The charge of the capacitor leaks away due to the reduction in the insulating power of the intervening medium,and the capacitor becomes useless.
The sharp ends of the conductor have a large electric charge density. The electric field near such a region is very strong. This strong electric field can strip the electrons from the surface of the metal; this event is called dielectric breakdown and is also known as corona discharge.
The maximum electric field up to which an insulating medium can maintain its insulating property is called the dielectric strength.
For air,the value of dielectric strength is about $3 \times 10^{6} \ V/m$,and this electric field corresponds to a potential difference of $3 \times 10^{4} \ V$ between conductors. Thus,for a capacitor to store a large amount of charge without leaking,its capacitance should be high.