# Series LC ckt question

In a series LC ckt, the capacitor charges to the applied voltage V after some time t1secs. Now there is no voltage across the inductor.
How can the inductor keep supplying current to the capacitor, when the potential difference across it is zero.
The capacitor is charged up to 2V. Why just 2V?

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I feel like I'm missing information. What's "2V" referring to? Is there a power source in this circuit? Do we charge the capacitor, then add it to the circuit after it's charged?

Well I have 2 cases:
1.
Just an LC circuit connected to a voltage source thru a switch.
switch is closed and capacitor is charged to supply voltage V.
Now the switch is opened, the inductor opposes this change and an emf is developed across it
which is equal to - L. di/dt
This will continue charging the capacitor in the -ve direction. Why does the capacitor get charged to 2 times V.

2. Just an LC ckt with a switch (no voltage source) with the capacitor charged to V volts. When the switch is closed, the capacitor starts discharging thru the inductor. When the cap current reaches zero, the inductor begins charging the cap. The capacitor is charged up to 2V.
why 2V. why not more. conservation of energy?