In the following network potential at ‘O’

CONCEPT:

• According to Ohm’s law: The potential difference across a resistor in a circuit is directly proportional to the current flowing in it.

V = R I

Where V is potential difference, R is resistance and I is current.

• Kirchhoff’s current law (KCL): It states that, the total current entering a circuit’s junction is exactly equal to the total current leaving the same junction.

EXPLANATION:

Let potential at O is V’ and all the current is originating from the point O.

According to the KCL, the sum of all the current originating from the point O will be equal to zero.

Use Ohm’s law to final total current originating from O:

Current in OA + Current in OB + Current in OC = 0

(V – 8)/2 + (V – 4)/4 + (V – 2)/2 = 0

(2 V – 16 + V – 4 + 2 V – 4)/ 4= 0

5 V – 24 = 0