Learn everything about Current Division in Parallel Circuits.

Current Divider Rule | Current Division Principle

Statement: The electrical current in a parallel circuit divides. The circuit divider rule explains the way in which the current at any node divides among the different branches.

Current Divider Formula

Let's consider an electrical circuit which contains a single current source and two parallel resistors. The current It enters the node. A parallel circuit has the same voltage across all components, but current always divide into parallel components. We are interested to find the current flowing through resistor Rx. The formula for current divider law is now:
current-divider-formula
Ix = (Rt/Rx) * It.
Where Ris the equivalent resistance of parallel resistors.

Current Divider Rule Examples

An electric circuit has two parallel resistors of 2 and 10 ohms. Apply the current divider equation to find the current flowing through both resistors when the input is 5 A.
current-divider-example
Let's consider another example where three parallel resistors of 1 Ω, 2 Ω, and 3 Ω are connected in parallel to 14 A source.
current-divider-example-2

Basic Useful concepts you should know

What is node, How it is formed in electric circuits

A node is a common point or a junction where two or more than two components are joined. The electrical node is a common point where two or more than two electronic components are joined.

What are parallel components and how to solve them

The components which are connected in the parallel configuration. Simply saying if heads of components share one common node and tails of components share other nodes then such components are referred as parallel components. Such components can be solved by using the formula:
(1/Rt) = (1/R1) + (1/R2) + ... (1/Rn)
For example, previously we solved 2-ohm resistor in parallel to 10-ohm resistor. Let's see how to do it:
(1/Rt) = (1/R1) + (1/R2)
(1/Rt) = (1/2 ohm) + (1/10 ohm)

(1/Rt) = 0.5 ohm + 0.1 ohm

and Rt = 1/0.6 ohms = 1.667 ohms

For our second example we used the formula:
(1/Rt) = (1/R1) + (1/R2) + (1/R3)
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