> [!summary]
Resistors are a component in circuits that reduce the flow of current.
>
**Key equations:**
>
Resistors in series:
$R_T = R_1 + R_2$
>
Resistors in parallel:
$\frac{1}{R_{T}}=\frac{1}{R_1}+\frac{1}{R_2}$
>[!info]+ Read Time
**⏱ 2 mins**
# Definition
Resistors are a type of object used in [[Circuits|circuits]]. They reduce the flow of [[Current|current]]. Current gets reduced because of the [[Insulators|insulating]] material that resistors are made of. It's common to call reducing the flow of electrons [[Resistance|resistance]] because of this.
Resistors reduce the flow of electrons by converting the energy of electron collisions into heat.
# Resistors In Series
![[res_1.png]]
[^1]
For resistors in series, the current through each resistor is the same. Since they share the same wire. This means that our total [[Potential Difference|potential difference]] of the circuit will be the potential difference of each resistor.
>[!warning] Assumption
Recall from [[Ohm's Law|ohm law]] that $V = IR$
$\begin{array}{c}
V_{T} = V_{1}+V_{2} + V_{3}\\
\cancel{I}R_T = \cancel{I}R_1 + \cancel{I}R_2 \\
R_T = R_1 + R_2
\end{array}$
# Parallel Resistors
![[res_2.png]]
[^2]
For resistors in parallel the [[Potential Difference|potential difference]] for each resistor is the same. Meaning that our total current is the sum of the junctions by [[Kirchhoff's Laws]].
>[!warning] Assumption
Recall from [[Ohm's Law|ohm law]] that $V = IR$
$
\begin{array}{c}
I_T = I_1 + I_2 \\
\frac{\cancel{V}}{R_T} = \frac{\cancel{V}}{R_2} + \frac{\cancel{V}}{R_2} \\
\frac{1}{R_{T}}=\frac{1}{R_1}+\frac{1}{R_2}
\end{array}
$
# Resources
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[^1]: Taken from https://tikz.net/electric_circuit_resistor/ by Izaak Neutelings (Februari, 2020)
[^2]: Adapted from https://tikz.net/electric_circuit_resistor/ by Izaak Neutelings (Februari, 2020)