Question

If the difference between the radii of the two spheres of a spherical capacitor is increased, state whether the capacitance will increase or decrease.

Answer 1

The capacitance of a spherical capacitor is C = 4πε₀\(\left(\frac{a b}{b-a}\right)\) where a and b are the radii of the concentric inner and outer conducting shells. Hence, the capacitance decreases if the difference b – a is increased.