In Ohm’s Law, which expression represents voltage?

• A. V = I x R
• B. I = V / R
• C. R = V / I
• D. P = V x I

Answer: (A)

Voltage is the electrical potential difference across a component, and Ohm’s Law links it to current and resistance with V = I × R. When you know the current flowing through a resistor and its resistance, multiplying I by R gives the voltage. For example, 3 A through a 4 Ω resistor yields 12 V. The other expressions describe different quantities: I = V / R gives current, R = V / I gives resistance, and P = V × I gives power.