Which expression correctly represents Ohm's Law relating voltage, current, and resistance?

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

Answer: (A)

Voltage, current, and resistance are linked by Ohm's Law: the voltage across a conductor equals the current through it times its resistance. This shows how voltage scales with current for a given resistance. For example, a 10-ohm resistor carrying 2 amperes has a voltage drop of V = I × R = 2 A × 10 Ω = 20 V. You can also rearrange to solve for the others: I = V / R or R = V / I. The other forms don’t fit because they either multiply voltage by resistance to get current (which mismatches units) or mix operations that don’t reflect the actual relationship (such as subtracting current from voltage or dividing resistance into voltage).