What letter is commonly used to represent voltage in electrical circuits?

In electrical circuits, voltage is commonly represented by the letter "V." Voltage, also known as electric potential difference, is a measure of the energy per unit charge and is essential for understanding how electrical circuits operate. The symbol "V" is widely accepted in scientific literature, educational materials, and practical applications, making it a standard notation in electronics and electrical engineering.

Understanding voltage is crucial, as it indicates how much electrical energy per charge is available to push electrons through a circuit. This distinction is vital for analyzing circuit behavior, such as calculating current flow and understanding the relationship between voltage, current, and resistance in accordance with Ohm's Law. The other choices represent different electrical parameters: "I" denotes current, "R" signifies resistance, and "E" can sometimes represent electromotive force, but "V" is the most universally recognized symbol for voltage.