Washington Esthetician State Board Practice Exam 2026 – Complete Prep Resource

The correct answer is Ohms because it relates to the resistance that a conductor provides to the flow of current. According to Ohm's Law, current (I) flowing through a conductor is directly proportional to the voltage (V) and inversely proportional to the resistance (R). This means that for current to flow, the voltage must be sufficient to overcome the resistance measured in ohms. If the force, or voltage, applied is not greater than the resistance, the current will not flow.

The other options represent units related to electrical phenomena but do not directly describe the threshold that must be overcome for current to flow. Joules measure energy, Watts measure power (the rate at which energy is used), and Amperes measure the flow of current itself. While these units are important in understanding electrical circuits, they do not specifically address the resistance aspect that must be exceeded for current to move through a conductor.