Question

If a moter has 4 poles and is operating at a frequency of 60Hz, its synchronous speed is

Select one:
O a. 240 rpm
O b. 480 rpm
O c. 1,200 rpm
O d. 1,800 rpm

Answer 1

d.

Step-by-step explanation:

The synchronous speed (Ns) of a motor with 4 poles and operating at a frequency of 60Hz can be calculated using the formula:

Ns = 120 x f / p

where f is the frequency in Hertz and p is the number of poles.

Plugging in the values, we get:

Ns = 120 x 60 / 4 = 1,800 rpm

Therefore, the answer is option d) 1,800 rpm.