**Current**

Symbol is I for Intensity

Measured in Amperes, colloquially Amps

Hydraulic analogy = gallons per hour

Meter used to measure current is usually called an Ammeter

Named after the French physicist Andre Ampere

**Voltage**

Symbol is V for Voltage or Volts, or E for Electromotive Force (EMF)

Measured in Volts, abbreviated V

Hydraulic analogy = water pressure

Named after the Italian physicist Alessandro Volta

**Resistance**

Symbol is R for Resistance

Measured in Ohms, abbreviated with the omega symbol

Named after the German physicist Georg Simon Ohm

**Power**

Symbol is P

Measured in Watts, abbreviated W

Named after the Scottish engineer James Watt

**Joule's law**

P=VI for DC

P=VIK for AC where K is the power factor from +1 to -1

Named after the British physicist James Joule

**Galvanometer**

The original Ammeter

Named after Luigi Galvani who had the concept of animal electricity, later disproved.

**Guglielmo Marconi**

Wireless transmission between the US and Great Britain January 18, 1903.

**Kirchhoff's Current Law**

The sum of currents entering and leaving a node equals zero.

Named after German physicist Gustav Robert Kirchhoff (1824-1887), a student of Gauss.

**Kirchhoff's Voltage Law**

The sum of branch Voltages around a loop equals zero.

Named after German physicist Gustav Robert Kirchhoff (1824-1887), a student of Gauss.

**Gauss**

The unit of measurement of magnetic strength.

Named after German scientist Carl Friedrich Gauss (1777-1855)

**Frequency**

Symbol is Hz. Prior to 1968 it was called cycles per second and the symbol was cps.

Named after the German physicist Heinrich Hertz (1857-1894)

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