Resistance - Class X

Resistors in Series: When resistors are joined from end to end, it is called in series. In this case, the total resistance of the system is equal to the sum of the resistance of all the resistors in the system.

Let total resistance = R

Resistance of resistors are R1, R2, R3, … Rn

Therefore, R = R1 + R2 + R3 + …………+ Rn

Resistors in parallel: When resistors are joined in parallel, the reciprocal of total resistance of the system is equal to the sum of reciprocal of the resistance of resistors.

Fig: Resistance in Series

Fig: Resistance in Parallel

Let total resistance = R

Resistance of resistors are R1, R2, R3, … Rn