Question

The reciprocal of resistance is conductance. The unit of resistance is ohm. Therefore, the unit of conductance is
(a). Ohm
(b). Henry
(c). Mho
(d). Moles litre

Answer 1

- Hint: First, one should know what the definition of resistance is. Resistance is the measure of opposition to current flow in the circuit. It is denoted by $R\alpha \dfrac{1}{I}$ . Its unit is omega $\left( \Omega \right)$. So, conductance is inverse of resistance.

Formula used: $R\propto \dfrac{1}{I}$, $R=\dfrac{1}{G}$

Complete step-by-step solution -
Conductance is the measure of how easily current is flowing in a certain path, while resistance tries the access flow of current in a certain path so that circuit or any device is not harmed by current.
The reciprocal relationship between conductance and resistance can be expressed as $R=\dfrac{1}{G}$ where G is the used to measure conductance and $G=\dfrac{1}{R}$ where R is resistance. The equation of resistance is $R\alpha \dfrac{1}{I}$
$R=\dfrac{V}{I}=\dfrac{volt}{Ampere}=omega\left( \Omega \right)$
Where V is taken as proportionality constant voltage and I is current.
Now unit of conductance G is given by
$G=\dfrac{1}{R}=\dfrac{1}{\Omega }=\mho$ also known as mho.
Example for calculating conductance: Conductance of a conductor with resistor 10ohm can be calculated as:
$G=\dfrac{1}{R}$
$G=\dfrac{1}{10}=0.1\mho$ (mho)
Thus, conductance is 0.1 mho.
Hence, the unit of conductance is mho. Option (c) is correct.

Note: Remember, another way to find conductance unit is as per set by International standard (SI) unit is Siemens which is explained as when current of 1A passes through components having voltage 1V then conductance will be current by voltage which will be equal to 1S (Siemens). So, don’t make mistakes in calculating the sum of resistance and conductance because there are chances of mistakes in using formula.