Electrical & electronic units of electric current, voltage, power, resistance, capacitance, inductance, electric charge, electric field, magnetic flux, frequency:
Electrical & electronic units table
Unit Name  Unit Symbol  Quantity 

Ampere (amp)  A  Electric current (I) 
Volt  V  Voltage (V, E) Electromotive force (E) Potential difference (Δφ) 
Ohm  Ω  Resistance (R) 
Watt  W  Electric power (P) 
Decibelmilliwatt  dBm  Electric power (P) 
DecibelWatt  dBW  Electric power (P) 
VoltAmpereReactive  var  Reactive power (Q) 
VoltAmpere  VA  Apparent power (S) 
Farad  F  Capacitance (C) 
Henry  H  Inductance (L) 
siemens / mho  S  Conductance (G) Admittance (Y) 
Coulomb  C  Electric charge (Q) 
Amperehour  Ah  Electric charge (Q) 
Joule  J  Energy (E) 
Kilowatthour  kWh  Energy (E) 
Electronvolt  eV  Energy (E) 
Ohmmeter  Ω∙m  Resistivity (ρ) 
siemens per meter  S/m  Conductivity (σ) 
Volts per meter  V/m  Electric field (E) 
Newtons per coulomb  N/C  Electric field (E) 
Voltmeter  V⋅m  Electric flux (Φ_{e}) 
Tesla  T  Magnetic field (B) 
Gauss  G  Magnetic field (B) 
Weber  Wb  Magnetic flux (Φ_{m}) 
Hertz  Hz  Frequency (f) 
Seconds  s  Time (t) 
Meter / metre  m  Length (l) 
Squaremeter  m^{2}  Area (A) 
Decibel  dB  
Parts per million  ppm 
Units prefix table
Prefix

Prefix Symbol 
Prefix factor 
Example 

pico  p  10^{12}  1pF = 10^{12}F 
nano  n  10^{9}  1nF = 10^{9}F 
micro  μ  10^{6}  1μA = 10^{6}A 
milli  m  10^{3}  1mA = 10^{3}A 
kilo  k  10^{ 3}  1kΩ = 1000Ω 
mega  M  10^{ 6}  1MHz = 10^{6}Hz 
giga  G  10^{ 9}  1GHz = 10^{9}Hz 
Electrical units definitions
Volt (V)
Volt is the electrical unit of voltage.
One volt is the energy of 1 joule that is consumed when electric charge of 1 coulomb flows in the circuit.
1V = 1J / 1C
Ampere (A)
Ampere is the electrical unit of electrical current. It measures the amount of electrical charge that flows in an electrical circuit per 1 second.
1A = 1C / 1s
Ohm (Ω)
Ohm is the electrical unit of resistance.
1Ω = 1V / 1A
Watt (W)
Watt is the electrical unit of electric power. It measures the rate of consumed energy.
1W = 1J / 1s
1W = 1V ⋅ 1A
Decibelmilliwatt (dBm)
Decibelmilliwatt or dBm is a unit of electric power, measured with logarithmic scale referenced to 1mW.
10dBm = 10 ⋅ log_{10}(10mW / 1mW)
DecibelWatt (dBW)
Decibelwatt or dBW is a unit of electric power, measured with logarithmic scale referenced to 1W.
10dBW = 10 ⋅ log_{10}(10W / 1W)
Farad (F)
Farad is the unit of capacitance. It represents the amount of electric charge in coulombs that is stored per 1 volt.
1F = 1C / 1V
Henry (H)
Henry is the unit of inductance.
1H = 1Wb / 1A
siemens (S)
siemens is the unit of conductance, which is the opposite of resistance.
1S = 1 / 1Ω
Coulomb (C)
Coulomb is the unit of electric charge.
1C = 6.238792×10^{18} electron charges
Amperehour (Ah)
Amperehour is a unit of electric charge.
One amperehour is the electric charge that flow in electrical circuit, when a current of 1 ampere is applied for 1 hour.
1Ah = 1A ⋅ 1hour
One amperehour is equal to 3600 coulombs.
1Ah = 3600C
Tesla (T)
Tesla is the unit of magnetic field.
1T = 1Wb / 1m^{2}
Weber (Wb)
Weber is the unit of magnetic flux.
1Wb = 1V ⋅ 1s
Joule (J)
Joule is the unit of energy.
1J = 1 kg ⋅ m^{2} / s^{2}
Kilowatthour (kWh)
Kilowatthour is a unit of energy.
1kWh = 1kW ⋅ 1h = 1000W ⋅ 1h
Kilovoltamps (kVA)
Kilovoltamps is a unit of power.
1kVA = 1kV ⋅ 1A = 1000 ⋅ 1V ⋅ 1A
Hertz (Hz)
Hertz is the unit of frequency. It measures the number of cycles per second.
1 Hz = 1 cycles / s
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