Question

A single metal sphere can be considered a capacitor. True or false. Explain.

Answer 1

False. A single metal sphere is a conductor and electric field inside a conductor is zero and so a potential difference can never be established for storing energy or charge. For a capacitor, an Electric field must be developed which is established with the use of a dielectric. Even in a parallel plate capacitor with no effective medium between the plates, the dielectric is in the form of air which creates an electric field by the relation:

E = - V/d

d = distance between the plates.