Hey, guys! I had a brief electromag question. If capacitance is defined as the amount of charge that can be stored in a capacitor per unit of potential difference, then technically can capacitors made from insulators still have a capacitance? The problem I'm considering is calculating the self-capacitance of a sphere in a vacuum. I first solve for the potential difference and then use the definition of capacitance to cancel the charge term and just have capacitance. However, if one considers the sphere to be conducting, then the charge is only stored on its surface. However, if the sphere is considered to be insulating, then the same charge is distributed throughout the sphere. If the charge density is assumed to be uniform, does it make sense to consider the problem with an insulating instead of conductive sphere?