Final answer:
Voltage, symbolized by 'V', measures the electric potential difference which pushes current through a conductor.
Step-by-step explanation:
The voltage, abbreviated as V and also known as the electric potential difference or potential, is the unit that measures the force or pressure that pushes an electric current through a conductor. Voltage can be likened to gravitational potential energy or to pressure in a fluid system. A higher voltage indicates the potential for more work to be done by moving charges, much like an object placed higher can potentially release more gravitational energy.
For instance, the potential difference or voltage across a battery's terminals can be described as its electromotive force (emf) when disconnected from a circuit, and this is also measured in volts. When connected in a circuit, it's known as the terminal potential difference. Moreover, Ohm's law illustrates a fundamental relationship in electrical circuits, affirming that the product of current (I) and voltage yields power.
Resistance is another crucial concept representing the opposition to current flow within a circuit, typically quantified in ohms (Ω). According to Ohm's law, for ohmic devices such as resistors, voltage (V) across the device is directly proportional to the product of the current (I) through the device and its resistance (R).