<--tecnología
ELECTRIC MAGNITUDES AND UNITS
MagnitudeUnit 
Electric Charge
Quantity of Electricity
QcoulombC 1 C = 6.24·1018 elementary charges (i.e.: electrons)
 
Electric currentIampere
amp
AI = Q / t ; 1A=1C/1s I = V/R ; 1A=1V/1Ω
Voltage
Electric Potencial
Potential Difference
Electromotive Force
V voltvV = E/Q ; 1V=1J/1C V = R · I ; 1V=1Ω·1A
Electric ResistanceRohmΩR = ρ * L / S ; L = length, S = area; R = V/I ; 1Ω = 1V/1A
 
PowerPwattWP = E/t ; 1W =1J/1sP = V · I ; 1W = 1V·1A
EnergyE
W
jouleJE = P · t
1 Kw·h = 1000 J/s · 3600 s = 3 600 000 J
 
Inductive ReactanceXLohmΩXL= 2 * π * f * L
Capacitive ReactanceXCohmΩXC=1 / ( 2 * π * f * C)
ImpedanceZohmΩ Z = SQR ( R2 + (2 * π * f * L - 1 / ( 2 * π* f * C) )2 )
 
CapacitanceCfaradF 
InductanceLhenryH 

π = pi = 3.14159265... f = frequency ω = omega = 2 * π * f XL= ω* L XC=1 / ( ω* C) Z = SQR ( R2 + (ω * L - 1 / (ω * C) )2 )