Formula: Equivalent resistance of a series connection of resistors Equivalent resistance    Single resistance

Formula: Equivalent resistance of a series connection of resistors
Series connection of three resistors

Equivalent resistance

Unit
The total resistance (equivalent resistance) of a series circuit is the sum of individual resistors. For example, if you have a series circuit with three resistances \(R_1\), \(R_2\) and \(R_3\), then the total resistance \(R\) is given by: \[ R ~=~ R_1 ~+~ R_2 ~+~ R_3 \]

For example, if the first resistance is \(R_1 = 200 \, \Omega \), the second resistance is \(R_2 = 50 \, \Omega \), and the third resistance is \(R_3 = 100 \, \Omega \), then the total resistance of the series circuit is: \begin{align} R &~=~ 200 \, \Omega ~+~ 50 \, \Omega ~+~ 100 \, \Omega \\\\ &~=~ 350 \, \Omega \end{align}

Single resistance

Unit
One of the resistances of the series circuit.

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