What is the abbreviation for voltage?

• A. I
• B. V
• C. R
• D. E

Answer: (D)

Voltage is the electric potential difference and is most commonly written with the letter V. In circuit notation, current is I, resistance is R, and electromotive force (the source’s internal energy per charge) is often denoted by E. While E can describe a source’s emf, the standard symbol used for the voltage across a element or across a circuit is V. This is why Ohm’s law is written as V = IR, with V representing voltage, I current, and R resistance. The volt, the unit of voltage, is also abbreviated with V, reinforcing this convention.