In a three-phase power system, how many alternating currents are being used?

• A. Two
• B. Three
• C. Four
• D. One

Answer: (B)

In a three-phase power system, three separate alternating currents are utilized, each differing in phase by 120 degrees. This design allows for a more efficient and balanced delivery of electrical power compared to single-phase systems. The presence of three phases enables a continuous and smooth power supply, as one phase reaches its peak while the others are at different points in their cycle. This balance minimizes fluctuations in power delivery, which can be particularly beneficial for operating motors and other machinery that require stable power input. Overall, the use of three alternating currents is fundamental to the performance and reliability of three-phase systems, making this answer accurate.