Consider a parallel-plate capacitor with charge +q on the top plate and –q on the other, and a plate area that is large
relative to the separation distance. Contrast this with a spherical capacitor consisting of two concentric spherical shells,
one smaller than the other, with a charge of +q uniformly distributed on the outer shell and a charge of –q uniformly
distributed on the inner shell. (a) Do the positive and negative charges distribution contribute equally to the electric eld
inside each capacitor? If not, what fraction of the eld comes from the negative distribution? (b) What is the electric eld magnitude outside each capacitor?