Question

What is the law of combination of resistance in parallel

Answer 1

Answer:

Let Xs be the effective resistance of the two resistors in series, and V be the potential difference across the ends. Thus, when a number of resistors are connected in series, the effective resistance is equal to the sum of the individual resistances. This is called the law of combination of resistances in series.

Answer 2

Answer:

Explanation:

The law of combination of resistances in parallel states that when two or more resistances are connected in parallel, the reciprocal of the equivalent resistance is equal to the sum of the reciprocals of all the individual resistances.

Thus, if R₁, R₂, R₃, etc are combined parallel then, the equivalent (resultant) resistance (R) is given by

1/R = 1/R₁ + 1/R₂ + 1/R₃ + and so on ..

For example, if two resistance of 5 Ω each are connected in parallel, the equivalent resistance (R) is given by,

1/R = 1/5 Ω + 1/5 Ω = 2/5 Ω (here, R₁ = R₂ = 5 Ω)

So, R = 5/2 = 2.5 Ω

So, when resistance are connected in parallel, the equivalent resistance is less then each individual resistance.