Capacitor

A parallel plate capacitor of capacitance \(12.5 \mathrm{~pF}\) is charged by a battery connected between its plates to potential difference of \(12.0 \mathrm{~V}\). The battery is now disconnected and a dielectric slab \((\epsilon_{\mathrm{r}}=6)\) is inserted between the plates. The change in its potential energy after inserting the dielectric slab is ________ \(\times10^{-12} \mathrm{~J}\).