electrical engineering
Capacitance
$$C = \frac{\epsilon A}{d}$$
Capacitor Charge
$$V = \frac{Q}{C}$$
Capacitor Current
$$I = C \frac{dV}{dt}$$
Capacitor Energy
$$E = \frac{1}{2} C V^2$$
Inductor Energy
$$E = \frac{1}{2} L I^2$$
Inductor Voltage
$$V = L \frac{dI}{dt}$$
Resistance in a straight conductor
$$R = \frac{\rho l}{A}$$
Shockley Diode Model
$$I = I_S \cdot (e^{\frac{V_D}{nV_T}} - 1)$$
Ohm's Law
$$V = IR$$