What formula is used to calculate voltage in a circuit?

This question tests your knowledge of the core Ohm's Law formula. In electronics, 'E' represents Electromotive force (voltage), 'I' represents current, and 'R' represents resistance. The fundamental formula for Ohm's Law states that voltage is equal to current multiplied by resistance. Therefore, the correct formula is E = I x R. If you use the Ohm's Law triangle (E on top, I and R on the bottom), covering the 'E' leaves 'I' and 'R' next to each other, which signifies multiplication. The distractors involving division are used to find current or resistance, and the options with squared values are related to calculating electrical power, not voltage.