A string with a length of 3.0 m has two adjacent resonances at frequencies 112 Hz and 140 Hz.
-Determine the fundamental frequency of the string.
A)14 Hz
B)28 Hz
C)42 Hz
D)56 Hz
E)70 Hz

Question

Quizplus · Accepted Answer

The difference between the two given frequencies (140 Hz - 112 Hz = 28 Hz) represents the frequency difference between adjacent harmonics. Since this string supports standing waves, the fundamental frequency (first harmonic) is the difference between these adjacent resonances, which is 28 Hz.

A String with a Length of 3