Pennsylvania Esthetician State Board Practice Exam

What name is given to a unit of electrical resistance?

1. Volt

2. Ohm

3. Watt

4. Farad

The correct answer is: Ohm

The unit of electrical resistance is called an Ohm. This unit is named after the German physicist Georg Simon Ohm, who formulated Ohm's Law, relating voltage, current, and resistance in electrical circuits. In this context, electrical resistance is a measure of how much a material opposes the flow of electric current. The higher the resistance measured in Ohms, the more difficult it is for electricity to flow through the material. Understanding the concept of resistance is crucial for an esthetician working with electrical devices during facial treatments or other services. It allows practitioners to ensure that the equipment operates safely and effectively, avoiding excessive heat generation or equipment damage. The other terms refer to different electrical measurements: a Volt is a unit of electrical potential; a Watt is a unit of power (which is calculated as voltage times current); and a Farad is a unit of capacitance, which describes the ability of a system to store electrical energy. Knowing these distinctions helps in the practical application of electrical knowledge in esthetics.