College Physics
posted by Robert .
Now we also know that the charge on a pair of parallel plates is proportional to the potential difference V, namely
q=CV.
We also know that the capacitance of two parallel plates is given by
C=ε0A/d,
where ε0=8.85×1012 is the permittivity of free space and d is the separation between the plates. Combine these equations and to get the force as a function of the potential. So now if you were to make a graph of force (F) vs. V2/d2, the slope of the graph would be
A) E
B) ε0A/2
C) C
D) ε0

It's B