AC polarity reversal at 60 Hz: True or False?

• A. It depends on load
• B. False
• C. True
• D. Only at high temperatures

Answer: (B)

AC voltage continuously reverses polarity as it follows a sinusoidal waveform. A reversal happens every half-cycle. At 60 Hz, one full cycle is 1/60 second, so half a cycle is 1/120 second (about 8.33 ms). That means the polarity flips 120 times per second. So the statement is true: polarity reversal occurs at 60 Hz. This behavior is inherent to AC and does not depend on load or temperature.