Water and Electricity

A 120V source is connected across the plates of a parallel-plate capacitor. The capacitor is being submerged vertically at constant speed into a container filled with water. What current in Amps flows through the voltage source during this process if it takes $$\tau=20 s$$ to totally submerge the capacitor? The capacitance (in air) of the capacitor is $$C_{0}=12\mu F$$ and water's relative permittivity is $\epsilon=81.$

Hint: If the capacitor is partially submerged at an instant of time try figuring out how to treat it as two separate capacitors at that instant.

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