Final answer:
The electric charge of the plate cannot be calculated with the provided information. Charge is the product of potential difference and capacitance, but we do not have relevant information to calculate capacitance in this case.
Step-by-step explanation:
To find the electric charge of the plate, we need to understand that the electric potential (V = 12 V) has no direct relationship with the physical dimensions of the plate. The electric property of the plate that would depend on the potential difference and its dimensions is the capacity. To find charge (Q), we need to know the capacitance (C) as charge is the product of voltage (V) and capacitance (C) i.e., Q = C*V.
A key equation in such considerations is C = ε* A/d where ε is the permittivity, A is the area of the plate and d is the distance between the plates. However, given the information in this question - specifically that it mentions the potential at 2 cm from the plate but not a second plate or a material in between - we can't be sure of the situation or the permittivity to use and thus the charge cannot be determined.
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