Question

Does the capacitance of a device depend on the applied voltage? What about the charge stored in it?

Short answer

No, voltage and charge have no effect on capacitance.

Step-by-step solution

Defining Capacitance

A capacitor is a device that can retain energy, in an electrical circuit and its ability to store energy in the form of charge is known as capacitance.

does capacitance depend upon stored charge and the potential difference?

The capacitance of a capacitor is solely determined by its shape, size and the material used in it.

For a parallel plate capacitor, the capacitance C, is given as

$\mathbf{C}\mathbf{=}\frac{{\mathbf{\epsilon }}_{\mathbf{o}}\mathbf{A}}{\mathbf{d}}$

where ${\mathrm{\epsilon }}_{\mathrm{o}}$is the permittivity of free space, A is the area between two parallel plates and d is the distance between two parallel plates.

As, changing the applied voltage results in more charge being accumulated on the capacitor plates. Their ratio remains the same, which is the capacitance.

Therefore, the capacitance of a device does not depend on the applied voltage and the charge stored in it.