ELECTROSTATICS
├── Electric Charge
│   ├── Properties
│   │   ├── Conservation (isolated system)
│   │   ├── Quantization: q = ne
│   │   └── Additive (algebraic sum)
│   └── Units: coulomb (C)
│
├── Coulomb's Law
│   ├── F = kq_{1}q_{2}/$r^{2}$
│   ├── k = $9 \times 10^{9}$ N $m^{2}$/$C^{2}$
│   ├── Superposition principle
│   └── Vector nature (attractive/repulsive)
│
├── Electric Field
│   ├── E = F/q_{0} = kQ/$r^{2}$
│   ├── Field lines (from +q, to −q, never cross)
│   ├── Configurations
│   │   ├── Point charge: E = kQ/$r^{2}$
│   │   ├── Dipole axial: E = 2kp/$r^{3}$
│   │   ├── Dipole equatorial: E = kp/$r^{3}$
│   │   └── Ring on axis: E = kQx/($R^{2}$+$x^{2}$)^(3/2)
│   └── Inside conductor: E = 0
│
├── Gauss's Law
│   ├── Φ = q_enc/ε_{0}
│   ├── Applications
│   │   ├── Infinite wire: E = λ/2πε_{0}r
│   │   ├── Infinite plane: E = σ/2ε_{0}
│   │   ├── Conducting sphere: E = kQ/$r^{2}$ (outside), 0 (inside)
│   │   └── Insulating sphere: E = kQr/$R^{3}$ (inside)
│   └── Requires high symmetry
│
├── Electric Potential
│   ├── V = kQ/r
│   ├── E = −dV/dr
│   ├── Equipotential surfaces ⊥ to E
│   ├── Dipole equatorial: V = 0
│   └── Work on equipotential: W = 0
│
└── Capacitors
    ├── C = Q/V = ε_{0}A/d (vacuum)
    ├── With dielectric: C = Kε_{0}A/d
    ├── Series: 1/C_eq = Σ1/Cᵢ
    ├── Parallel: C_eq = ΣCᵢ
    ├── Energy: U = ½$CV^{2}$ = $Q^{2}$/2C
    └── Dielectric insertion
        ├── Battery connected → V constant, C↑K, U↑K
        └── Battery disconnected → Q constant, C↑K, V↓K, U↓K