Question

Name the physical quantity of which the units are:
(i) Volt
(ii) Coulomb
(iii) Ohm
(iv) Ampere

Answer 1

Hint: We have been given with different units and asked to find their appropriate physical quantities. First of all, we will give the standard definition of these units. For example, we will use the definition of 1 Volt to find its standard physical quantity. Also, we will use the most common physical quantity for the particular unit as our answer.

Complete answer:
We will start by solving the first problem of our question and then we will move on in succession. This is done as follows:
(i) Volt: 1 Volt is defined as the electric potential generated between two points when 1 Ampere of current generates 1 Watt of power between these two points.
Therefore, the physical quantity whose unit is Volt is known as “Electric Potential”.
(ii) Coulomb: 1 Coulomb is defined as the amount of electric charge transferred by purely conducting wire having a current of 1 Ampere in a time period of 1 second.
Therefore, the physical quantity whose unit is Coulomb is known as “Electric charge”.
(iii) Ohm: 1 ohm is defined as the electrical resistance offered by the circuit when the circuit is connected across a voltage of 1 Volt and a current of 1 Ampere is flowing through it.
Therefore, the physical quantity whose unit is Ohm is known as “Electrical resistance”.
(iv) Ampere: 1 Ampere is defined as the electrical current that flows through a circuit when the circuit is connected across a voltage of 1 Volt and the resistance offered by this circuit is equal to 1 ohm.
Therefore, the physical quantity whose unit is Ampere is known as “Electrical Current”.

Note:
The basic definition of all the units are very important and should be thoroughly remembered. These definitions are used in deriving new formulas and proving hypotheses. These are also used to establish a relation between two unknown quantities, like we used ohm to establish a relation between voltage and current.