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Chapter 2: Voltage, Current, and Resistance

Concept Formula Citation
Voltage (V) $V = \frac{W}{Q}$ [1-3]
Current (I) $I = \frac{Q}{t}$ [4]
Conductance (G) $G = \frac{1}{R}$ [5]
Wire Resistance (R) $R = \rho \frac{l}{A}$ [6]

Chapter 3: Ohm’s Law, Energy, and Power

Concept Formula Citation
Ohm’s Law (Current) $I = \frac{V}{R}$ [7]
Ohm’s Law (Voltage) $V = IR$ [7]
Ohm’s Law (Resistance) $R = \frac{V}{I}$ [8]
Power (Definition) $P = \frac{W}{t}$ [9]
Watt’s Law (V and I) $P = VI$ [10, 11]
Watt’s Law (I and R) $P = I^2 R$ [10]
Watt’s Law (V and R) $P = \frac{V^2}{R}$ [10, 11]

Chapter 4: Series Circuits

Concept Formula Citation
Kirchhoff’s Voltage Law (KVL) $\sum_{i=1}^{n} V_i = 0$ [12]
Voltage Divider Rule (for $V_2$) $V_2 = V_S \left(\frac{R_2}{R_T}\right)$ [13]

Chapter 5: Parallel Circuits

Concept Formula Citation
Total Parallel Resistance (General) $\frac{1}{R_T} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} + \dots + \frac{1}{R_n}$ [14]
Total Parallel Resistance (Product-Over-Sum, 2 R) $R_T = \frac{R_1 R_2}{R_1 + R_2}$ [15]
Current Divider (for $I_1$ in 2 resistors) $I_1 = I_T \left(\frac{R_2}{R_1 + R_2}\right)$ [16]
Current Divider (for $I_2$ in 2 resistors) $I_2 = I_T \left(\frac{R_1}{R_1 + R_2}\right)$ [16]

Chapter 6: Series-Parallel Circuits

Concept Formula Citation
Thevenin Voltage (using V-Divider) $V_{TH} = V_S \left(\frac{R_2}{R_1 + R_2}\right)$ [17]
Load Voltage (using Thevenin) $V_L = V_{TH} \left(\frac{R_L}{R_{TH} + R_L}\right)$ [18]

Chapter 8: Introduction to Alternating Current and Voltage

Concept Formula Citation
Period/Frequency Relationship $T = \frac{1}{f}$ and $f = \frac{1}{T}$ [19]
Degrees to Radians $\text{rad} = \text{degrees} \times \frac{\pi}{180}$ [20]
Radians to Degrees $\text{degrees} = \text{rad} \times \frac{180}{\pi}$ [20]
Instantaneous Voltage (No phase shift) $v = V_p \sin \theta$ [21]
Instantaneous Voltage (With phase shift) $v = V_p \sin (\theta \pm \phi)$ [22]
Peak-to-Peak Voltage $V_{pp} = 2 \times V_p$ [23]
RMS Voltage $V_{rms} = 0.707 \times V_p$ [23, 24]
Average Voltage (Half-wave) $V_{avg} = 0.637 \times V_p$ [25]
AC Power (Watt's Law - V and I) $P = V_{rms} I_{rms}$ [26]
AC Power (Watt's Law - V and R) $P = \frac{V_{rms}^2}{R}$ [26]
AC Power (Watt's Law - I and R) $P = I_{rms}^2 R$ [26]

Chapter 9: Capacitors

Concept Formula Citation
Capacitance (C) $C = \frac{Q}{V}$ [27]
Charge Stored (Q) $Q = CV$ [27, 28]
Energy Stored (W) $W = \frac{1}{2} C V^2$ [28]
Capacitance (Physical) $C = \epsilon_r \left(8.85 \times 10^{-12} \text{ F/m}\right) \left(\frac{A}{d}\right)$ [29, 30]
Series Capacitance (Reciprocal Sum) $\frac{1}{C_T} = \frac{1}{C_1} + \frac{1}{C_2} + \dots + \frac{1}{C_n}$ [31]
Series Capacitance (Product-Over-Sum, 2 C) $C_T = \frac{C_1 C_2}{C_1 + C_2}$ [31]
Parallel Capacitance (Sum) $C_T = C_1 + C_2 + C_3 + \dots + C_n$ [32]
Capacitive Reactance ($X_C$) $X_C = \frac{1}{2\pi fC}$ [33]
Total Series Reactance $X_{C_{tot}} = X_{C1} + X_{C2} + X_{C3} + \dots + X_{C_n}$ [33]
Total Parallel Reactance (Reciprocal Sum) $\frac{1}{X_{C_{tot}}} = \frac{1}{X_{C1}} + \frac{1}{X_{C2}} + \dots + \frac{1}{X_{C_n}}$ [34]
Capacitive Voltage Divider ($V_{out}$ using $X_C$) $V_{out} = V_S \left(\frac{X_{C2}}{X_{C_{tot}}}\right)$ [35]
Capacitive Voltage Divider ($V_{out}$ using $C$) $V_{out} = V_S \left(\frac{C_{tot}}{C_2}\right)$ [36]
Concept Formula Citation
Voltage (V) $V = \frac{W}{Q}$ [1-3]
Current (I) $I = \frac{Q}{t}$ [4]
Conductance (G) $G = \frac{1}{R}$ [5]
Wire Resistance (R) $R = \rho \frac{l}{A}$ [6]
Concept Formula Citation
Ohm’s Law (Current) $I = \frac{V}{R}$ [7]
Ohm’s Law (Voltage) $V = IR$ [7]
Ohm’s Law (Resistance) $R = \frac{V}{I}$ [8]
Power (Definition) $P = \frac{W}{t}$ [9]
Watt’s Law (V and I) $P = VI$ [10, 11]
Watt’s Law (I and R) $P = I^2 R$ [10]
Watt’s Law (V and R) $P = \frac{V^2}{R}$ [10, 11]
Concept Formula Citation
Kirchhoff’s Voltage Law (KVL) $\sum_{i=1}^{n} V_i = 0$ [12]
Voltage Divider Rule (for $V_2$) $V_2 = V_S \left(\frac{R_2}{R_T}\right)$ [13]
Concept Formula Citation
Total Parallel Resistance (General) $\frac{1}{R_T} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} + \dots + \frac{1}{R_n}$ [14]
Total Parallel Resistance (Product-Over-Sum, 2 R) $R_T = \frac{R_1 R_2}{R_1 + R_2}$ [15]
Current Divider (for $I_1$ in 2 resistors) $I_1 = I_T \left(\frac{R_2}{R_1 + R_2}\right)$ [16]
Current Divider (for $I_2$ in 2 resistors) $I_2 = I_T \left(\frac{R_1}{R_1 + R_2}\right)$ [16]
Concept Formula Citation
Thevenin Voltage (using V-Divider) $V_{TH} = V_S \left(\frac{R_2}{R_1 + R_2}\right)$ [17]
Load Voltage (using Thevenin) $V_L = V_{TH} \left(\frac{R_L}{R_{TH} + R_L}\right)$ [18]
Concept Formula Citation
Period/Frequency Relationship $T = \frac{1}{f}$ and $f = \frac{1}{T}$ [19]
Degrees to Radians $\text{rad} = \text{degrees} \times \frac{\pi}{180}$ [20]
Radians to Degrees $\text{degrees} = \text{rad} \times \frac{180}{\pi}$ [20]
Instantaneous Voltage (No phase shift) $v = V_p \sin \theta$ [21]
Instantaneous Voltage (With phase shift) $v = V_p \sin (\theta \pm \phi)$ [22]
Peak-to-Peak Voltage $V_{pp} = 2 \times V_p$ [23]
RMS Voltage $V_{rms} = 0.707 \times V_p$ [23, 24]
Average Voltage (Half-wave) $V_{avg} = 0.637 \times V_p$ [25]
AC Power (Watt's Law - V and I) $P = V_{rms} I_{rms}$ [26]
AC Power (Watt's Law - V and R) $P = \frac{V_{rms}^2}{R}$ [26]
AC Power (Watt's Law - I and R) $P = I_{rms}^2 R$ [26]
Concept Formula Citation
Capacitance (C) $C = \frac{Q}{V}$ [27]
Charge Stored (Q) $Q = CV$ [27, 28]
Energy Stored (W) $W = \frac{1}{2} C V^2$ [28]
Capacitance (Physical) $C = \epsilon_r \left(8.85 \times 10^{-12} \text{ F/m}\right) \left(\frac{A}{d}\right)$ [29, 30]
Series Capacitance (Reciprocal Sum) $\frac{1}{C_T} = \frac{1}{C_1} + \frac{1}{C_2} + \dots + \frac{1}{C_n}$ [31]
Series Capacitance (Product-Over-Sum, 2 C) $C_T = \frac{C_1 C_2}{C_1 + C_2}$ [31]
Parallel Capacitance (Sum) $C_T = C_1 + C_2 + C_3 + \dots + C_n$ [32]
Capacitive Reactance ($X_C$) $X_C = \frac{1}{2\pi fC}$ [33]
Total Series Reactance $X_{C_{tot}} = X_{C1} + X_{C2} + X_{C3} + \dots + X_{C_n}$ [33]
Total Parallel Reactance (Reciprocal Sum) $\frac{1}{X_{C_{tot}}} = \frac{1}{X_{C1}} + \frac{1}{X_{C2}} + \dots + \frac{1}{X_{C_n}}$ [34]
Capacitive Voltage Divider ($V_{out}$ using $X_C$) $V_{out} = V_S \left(\frac{X_{C2}}{X_{C_{tot}}}\right)$ [35]
Capacitive Voltage Divider ($V_{out}$ using $C$) $V_{out} = V_S \left(\frac{C_{tot}}{C_2}\right)$ [36]
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