Polarity is the property of having which poles of an electric current?

• A. Positive and Negative
• B. Single and Double
• C. Beginning and End
• D. Small and Large

Answer: (A)

Polarity means there are two opposite poles in an electric current: the positive and the negative. In direct current, current flows from the positive pole toward the negative pole, and devices or electrodes are designed with this orientation in mind. The term captures the idea of two opposite charges, which is what polarity describes. The other options don’t reflect this electrical property, since they refer to size or sequence rather than opposing charges. In esthetics, using the correct positive or negative electrode ensures the current flows as intended and the skin effects are achieved safely.