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10:01
Hi
After all, either I wasn't able to understand you the whole time, or I simply tend to disagree with you
the equation $\frac{q}{C_0} - \frac{q_0 - q}{C} = - L q''$ is just as correct as $\frac{q}{C_0} - \frac{q_0 - q}{C} = L q''$
Current reference direction can be chosen arbitrarily
And even though it gives different results, the physical implications are the same
In fact, I got $\frac{q}{C_0} - \frac{q_0 - q}{C} = - L q'' = V_0 cos(\omega t)$

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