Calculating the capacitance problem

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The discussion revolves around calculating the ratio C/A for a parallel-plate capacitor connected to a battery, where the depth d of electron movement is analyzed against the potential difference V. The user combines the equations q=ε₀EA and q=CV to derive C/A=ε₀/D, but is unable to find a numerical solution. Clarification is sought on the meaning of "the depth from which the electrons come" and the significance of the gradient value of 5x10-14, including its units. Understanding these concepts is essential for solving the capacitance problem effectively.
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Homework Statement


If an uncharged parallel-plate capacitor (capacitance C) is connected to a battery, one plate becomes negatively charged as electrons move to the plate face (area A). The depth d from which the electrons come in the plate in a particular capacitor is plotted against a range of values for the potential difference V of the battery. When d is one picometre, the potential difference is 20V. The gradient is equal to 5x10-14. What is the ratio C/A.

Homework Equations



q=ε₀EA
q=CV

The Attempt at a Solution



I combined the above two equations to get the expressions C/A=ε₀/D
However that doesn't provide me with a numerical solution for the ratio C/A.

Can anyone please help?
 
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I don't understand what is meant by "the depth ... from which the electrons come in the plate".

Also, what is this "gradient equal to 5x10-14" mean? And what are the units?
 

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