**1. The problem statement, all variables and given/known data**

Assume we have two neutral plates a small distance away from each other. We place charge Q on one plate, leaving the other plate uncharged. We then measure a potential difference V across the plates. Some bright student notes the ratio of Q and V is not the value of the capacitance. What is the value of the capacitance?

**2. Relevant equations**

C = Q/V

**3. The attempt at a solution**

So I understand that capacitance is a geometric property of the object and what it is made of. But for this question I think that since only one of the plates is charged, therefore the Q in the equation would really only be Q/2 thus the ratio would be C = Q/2V.

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