Question

Potential difference between points A and B (i.e. ${V_A}$-${V_B}$ is ___________

Answer 1

We are asked to find the potential difference between the points A and B. To find out the potential difference between points A and B, take a path of the circuit from point A to B and calculate the potential for the path to get the required potential difference.

Complete step by step answer:
Given a circuit and we are asked to find the potential difference between points A and B.Let us redraw the circuit.

To find the potential difference between points A and B, we take the path ACDB.
Let ${V_A}$ be the potential at point A and ${V_B}$ be the potential at point B.
So, using the path ACDB the potential difference between point A and B is,
${V_A} - {V_B} = 2{\text{V}} + 6{\text{V}} - 4{\text{V}}$
$\Rightarrow {V_A} - {V_B} = 8{\text{V}} - 4{\text{V}}$
$\therefore {V_A} - {V_B} = 4{\text{V}}$

Therefore, the potential difference between points A and B is $4{\text{V}}$.

Note: Potential difference between two points A and B can be defined as the change in amount of potential energy of a charge while moving from point A to point B. Potential difference is also known as voltage drop. The SI unit of potential difference is volts. The relationship between voltage, current and resistance is given by Ohm’s law, which states that current passing through a conductor is directly proportional to the potential difference across the conductor. Mathematically, it is written as, $V = IR$ where $V$ is the potential difference or voltage drop, $I$ is the current and $R$ is the resistance of the conductor. If the voltage increases then there will be an increase in current flow too.