What is the synchronous speed of a twenty-four pole, 60Hz alternator?

To find the synchronous speed of an alternator, you can use the formula:

[

\text{Synchronous Speed (RPM)} = \frac{120 \times \text{Frequency (Hz)}}{\text{Number of Poles}}

]

In this case, the alternator has 24 poles and operates at a frequency of 60 Hz. Plugging these values into the formula gives us:

[

\text{Synchronous Speed} = \frac{120 \times 60}{24}

]

Calculating that:

[

\text{Synchronous Speed} = \frac{7200}{24} = 300 \text{ RPM}

]

Thus, the correct calculation leads to a synchronous speed of 300 RPM. This value represents the speed at which the magnetic field inside the alternator rotates, allowing the alternator to generate electricity efficiently. Understanding synchronous speed is fundamental in electrical engineering, particularly when dealing with alternators and synchronous motors, as it directly influences their operation and performance.