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Electric potential is a fundamental concept in physics, relating to the energy per unit charge due to an electric field. An analogy often used is to think of electric potential as electric 'height'. Just as a ball gains potential energy when raised against gravity, a charge gains electrical potential energy when moved against an electric field.

To understand this concept better, consider the formula:
\[ V = \frac{W}{Q} \]
Here, \(V\) represents the electric potential or voltage in volts, \(W\) is the energy in joules, and \(Q\) is the charge in coulombs. This equation tells us that the electric potential is the energy required to move a charge in an electric field; the higher the voltage, the more energy per charge is available for work.

Electromotive force, often abbreviated as EMF, is the energy provided per charge that drives the flow of electrons in a circuit. It's a bit like a battery's 'push' or force that sets electrons in motion, creating a current. Although the term includes 'force', it is actually a measure of energy per unit charge, just like voltage.

The EMF is the maximum potential difference between two electrodes of a battery or generator when no current is flowing. In a circuit, the EMF is equal to the voltage across the open circuit—no energy is being converted from electrical energy to other forms when no current flows.

Considering the kinetic energy of electrons, we delve into the core of quantum mechanics and solid-state physics. When an electron moves through an electric potential difference, it changes its kinetic energy because work is done on it.

The kinetic energy acquired by an electron as it moves through a potential difference of one volt is one electron volt (\(1 \text{eV}\)). The beauty of this measurement is that it simplifies the energy calculations at the atomic and subatomic levels where traditional units like joules can be inconveniently large. Hence, the electron volt is incredibly useful in contexts such as semiconductor physics and other realms involving fine-scale energy changes.

The International System of Units (SI) provides a standard for measuring and expressing physical quantities. It enables scientists and engineers worldwide to communicate findings with consistent and clear terms. The SI unit for electric potential is the volt (\(V\)), and the joule (\(J\)) is the SI unit for energy.

It is essential to note that while they are used together, volts and electron volts serve different roles: volts relate to the potential difference and electromotive force, whereas electron volts pertain to the energy an electron carries. Although not an SI unit, the electron volt is widely accepted in the scientific community because of its convenience in measuring small amounts of energy at the particle level.