Current

I = dQ/dt

The rate of change of charge with time.

Ampere = Coulomb / second

1 Coulomb = Chage of 6.24E18 electrons

Voltage

1V = 1 Joule / Coulomb

Amount of work to move one Coulomb

Capacitance

C = Q / V

Ohm's Law

V = I R

Power

P = V I = R I ² = V ² / R

Impedance

Z_R = R

Z_L = j 2 Π f L

Z_C = 1 / j 2 Π f C

I = Current

Q = Charge

V = Voltage

J = Joules

C = Capacitance

R = Resistance

Z = Impedance

L = Inductance

f = Frequency

j = imaginary