What term is used to express the amount of electrical energy stored in an electrostatic field?

The term used to express the amount of electrical energy stored in an electrostatic field is measured in joules. Joules are the standard unit of energy in the International System of Units (SI), and when discussing electrostatic fields, they provide a clear measurement of the work done to move charges within that field.

In the context of electrostatics, when discussing energy storage, joules becomes particularly relevant when calculations involve voltage and charge. For example, the energy stored in a capacitor, which generates an electrostatic field, can be calculated using the formula ( \frac{1}{2}CV^2 ) where ( C ) is capacitance in farads and ( V ) is voltage in volts. Thus, the result is naturally expressed in joules.

Other terms in the choices relate to different concepts; for example, coulombs measure charge rather than energy. Farads measure capacitance, which is related to the ability of a device to store electrical energy but does not itself quantify energy. Energy units is a general term that could refer to various types of energy measurement, but the specific term for electrical energy stored in an electrostatic field is precisely expressed in joules.