If the period of an AC sine wave is 180 ms, the frequency is

f=1/T=1/10⁻³=1000 Hz

Period (P) = 1/F

To determine the frequency of an alternating current (AC) sine wave when given the period, you can use the formula:

Frequency = 1 / Period

In this case, the period is given as 180 ms (milliseconds).

To find the frequency, plug in the given period value into the formula:

Frequency = 1 / (180 ms)

Note: It's essential to convert the period to seconds before calculating the frequency.

To convert milliseconds to seconds, divide the period value by 1000:

Frequency = 1 / (180 ms / 1000)

Simplifying this equation:

Frequency = 1 / (0.18 s)

Evaluating the expression:

Frequency = 5.56 Hz (rounded to two decimal places)

Therefore, the frequency of the AC sine wave is approximately 5.56 Hz.