In Ohm's Law, how is current related to voltage and resistance?

• A. I = V / R
• B. I = R / V
• C. I = V * R
• D. I = V + R

Answer: (A)

Current is how much charge flows per second, and Ohm’s Law links that flow to the pushing force (voltage) and the opposition (resistance). The current equals the voltage divided by the resistance, so more voltage pushes more current, while more resistance reduces it. For example, with 12 volts across 6 ohms, I = 12/6 = 2 amperes. If the resistance doubles to 12 ohms with the same voltage, I drops to 1 ampere. If you increase the voltage to 24 volts with the same 6 ohms, I becomes 4 amperes. The units align as volts per ohm, which equals amperes. In real devices, resistance can change with temperature or voltage, so the exact current can vary, but at any instant the relationship I = V/R holds with the current resistance value.