A circuit has self-inductance ' L ' and carries a current ' I '. To prevent sparking when the circuit is switched off, a capacitor which can withstand potential difference ' V ' is used. The least capacitance is

Step-by-step solution

The energy stored in the inductance is given by U = 1 2 LI ^2 Energy stored by the capacitor is given by W = 1 2 CV ^2 This energy must be transferred to the capacitor. aligned & 1 2 CV ^2= 1 2 LI ^2 & C = L ( I V )^2 aligned