\[R_T=\frac{R_1R_2}{R_1+R_2}\]
Variables
Rttotal parallel resistance (ohm)
R1resistance 1 (ohm)
R2resistance 2 (ohm)
Description
What is this formula?
This formula calculates the equivalent resistance of two resistors connected in parallel.
When to use it
Use it when analyzing electrical circuits where multiple resistors share the same voltage across parallel branches.
Example
Data:
R1 = 12 ohm
R2 = 18 ohm
Formula:
Rt = (R1*R2)/(R1+R2)
Substitution:
Rt = (12*18)/(12+18)
Result:
Rt = 7.2 ohm
Applications
Electrical engineering, circuit analysis, electronics, resistor networks, power distribution, and educational physics.