Voltage(symbol: V, measured in volts) expresses the difference in electric potential energy

• Voltage = joules/coulomb(how much work we can extract per charge)
• In the commonly used water analogy – the “water pressure”

Intensity of the current expresses the rate of flow of a charge

• in our water analogy – the rate of flow – as an equation I = q/t = charge/time

Charge (Unit is coulomb, common secondary unit is the elementary charge, e(charge of 1 electron)

Note – Faraday’s constant, 96485 coulomb/mole, is the number of coulomb carried by a mole of electron