Learn everything about Current Division in Parallel Circuits.

Current Divider Formula [Formulas Infographic Included]

Previously we studied the basic current divider rule along with formulas and examples. In this formula sheet, you'll learn other equations and all formulas for the cdr rule.
General Current divider formula
For current across unknown resistor Ix =
Rt / Rx
* It
Current divider formula for 2 Resistors
For current across first one I1 =
Rt / R1
* It
For current across second one I2 =
Rt / R2
* It
Alternative CDR Equation for 2 Resistors
For current across first one I1 =
R2 / R1 + R2
* It
For current across second one I2 =
R1 / R1 + R2
* It
CDR Formula for 3 Resistors
For current across first one I1 =
Rt / R1
* It
For current across second one I2 =
Rt / R2
* It
To current across third resistor I3 =
Rt / R3
* It
Where in above equation:
1 / Rt
=
1 / R1
+
1 / R2
+
1 / R2
Let's directly move to current divider formula sheet:
current-divider-formula-sheet
While solving the current divider example problem someone might confuse the general formulas for CDR and alternative forms However both these formulas are actually same. We can easily obtain:
I1 = (R2/(R1 + R2)) * It from I1 = (Rt/R1) * It

Just replace Rt by (R1.R2 / (R1 + R2)).
So that was all equations which you should remember while doing CDR.