What is Ohm's law equation?

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

Answer: (A)

Voltage, current, and resistance are linked by Ohm's law in a simple proportional way: voltage equals current through a conductor times its resistance. This direct form shows how voltage drives current through a given resistor. If you double the voltage while keeping the same resistance, the current doubles; if you double the resistance with the same voltage, the current halves. For example, with a 12 V source and a 6 Ω resistor, the current is 12/6 = 2 A.

A form that says current equals voltage times resistance would mislead with units and behavior, since volts times ohms does not yield amperes. Another valid rearrangement is resistance equals voltage divided by current, which expresses the same relationship in a different way. The expression P = V × I corresponds to electrical power, not the direct V–I–R relationship.