Define $1$ ohm, $1$ volt, and $1$ ampere briefly.

Hint:In physics, ohm is a SI unit of resistance and its symbol is $\Omega $ . Volt is a SI unit used for potential difference or called voltage of a cell and it’s denoted by $V$ . Ampere is a SI unit used for current which is rate of flow of charges and it’s denoted by $A$.

Complete answer:
Let us first understand the Ohm’s law of electricity which states that “In a given resistance across two points if potential difference is $V$ and current is $I$ then the resistance $R$ is related as $R = \dfrac{V}{I}$ “.

1 Ohm: One ohm can be defined as the resistance between two points which have a potential difference of $1$ volt and having a current of $1$ ampere across it. And it can be expressed from ohm’s law of electricity as $\text{1 ohm} = \dfrac{\text{1 volts}}{\text{1 ampere}}$.

1 Volt: The amount of work done in bringing a unit test positive charge from one point to another is known as potential difference so, $\text{1 Volt} = \dfrac{\text{1 Joule}}{\text{1 Coulomb}}$.

1 Ampere: Ampere is a unit of current which is a measurement of rate of flow of charges with respect to time, so one ampere is the current when one coulomb charges moves in one second. $1\,ampere = \dfrac{\text{1 Coulomb}}{{1\,\sec }}$ .

Note:Remember, all three physical quantities can be expressed together only with the help of ohm’s law of electricity as $\text{1 ohm} = \dfrac{\text{1 volts}}{\text{1 ampere}}$ . And the number of charges in one coulomb is equal to $6.24 \times {10^{18}}$ charges. All three physical quantities ohm, Volts and ampere are scalar quantities.