Which statement expresses Ohm's law?

Which statement expresses Ohm's law?

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

Answer: (D)

Ohm's law describes how voltage, current, and resistance relate in a conductor: V = I × R. This means the voltage across a resistor equals the current through it times its resistance, and you can rearrange to I = V / R or R = V / I. The statement that matches this relationship directly is V = I × R. The other forms don’t fit Ohm's law: I = V × R would mean current grows with both voltage and resistance in a way that isn’t consistent with the defining relation; R = V × I would imply resistance increases with voltage and current, which isn’t how resistance behaves for a given device; and P = V / I is not Ohm's law—power is P = V × I (or P = I^2 × R, or P = V^2 / R). For a quick check, a 10-ohm resistor with 5 volts gives I = V / R = 0.5 A, which satisfies V = I × R.

Ohm's law describes how voltage, current, and resistance relate in a conductor: V = I × R. This means the voltage across a resistor equals the current through it times its resistance, and you can rearrange to I = V / R or R = V / I. The statement that matches this relationship directly is V = I × R. The other forms don’t fit Ohm's law: I = V × R would mean current grows with both voltage and resistance in a way that isn’t consistent with the defining relation; R = V × I would imply resistance increases with voltage and current, which isn’t how resistance behaves for a given device; and P = V / I is not Ohm's law—power is P = V × I (or P = I^2 × R, or P = V^2 / R). For a quick check, a 10-ohm resistor with 5 volts gives I = V / R = 0.5 A, which satisfies V = I × R.