What is the frquency of vibration if the balance wheel of a wrist watch makes 90 revolutions in 25s?

A. 0.01 Hz
B. 0.04 Hz
C. 2.27 Hz
D. 3.60 Hz

Correct Answer:

Option D – 3.60 Hz

Explanation

Frequency = (No. of revolutions)/ Time = (90)/25 = 3.6 Hz