Ohm's Law relates which three electrical quantities?

• A. Voltage, current, and resistance
• B. Frequency, wavelength, and velocity
• C. Power, energy, and charge
• D. Capacitance, inductance, and impedance

Answer: (A)

Ohm's Law describes how voltage, current, and resistance are connected in a conductor. It states that the current flowing through a circuit is equal to the voltage across the conductor divided by its resistance (I = V / R), and equivalently that voltage equals current times resistance (V = I × R).

Think of voltage as the electrical push that drives charges, current as the rate at which those charges move, and resistance as the property of the material that opposes that movement. Because of this relationship, changing one of the quantities while keeping the others fixed changes the others in predictable ways. For example, doubling the voltage across the same resistor doubles the current; doubling the resistance with the same voltage halves the current.

A quick check: if you have 12 volts across a 6-ohm resistor, the current is I = V / R = 12 V / 6 Ω = 2 A, which also satisfies V = I × R (12 V = 2 A × 6 Ω).

The other option groupings describe different concepts: frequency, wavelength, and velocity are wave properties; power, energy, and charge involve energy and charge transfer; capacitance, inductance, and impedance relate to how circuits respond to AC signals, with impedance being a broader concept that extends beyond simple resistance. But the trio directly tied together by Ohm's Law is voltage, current, and resistance.