What is the formula to calculate voltage in a circuit?

The correct formula to calculate voltage in a circuit is derived from Ohm's Law, which states that voltage (V) is equal to the current (A) multiplied by the resistance (R). This relationship highlights how voltage is directly proportional to both the current flowing through the circuit and the resistance of the circuit components.

In the context of electrical circuits, when you increase the current while keeping the resistance constant, the voltage will also increase. Similarly, if you have a specific voltage and increase the resistance, the current will decrease if the total voltage remains unchanged.

The other formulas presented don't reflect this standard relationship. The formula representing voltage as the product of current and resistance is essential in understanding how electrical circuits function, making it fundamental knowledge in both theoretical and applied aspects of radiography and electrical engineering.