A string,0.28 m long and vibrating in its third harmonic,excites an open pipe that is 0.82 m long into its second overtone resonance.The speed of sound in air is 345 m/s.The speed of transverse waves on the string is closest to
A) 120 m/s.
B) 110 m/s.
C) 100 m/s.
D) 98 m/s.
E) 91 m/s.

Question

Quizplus · Accepted Answer

The third harmonic of the string has a wavelength of 2L/3, where L is the length of the string. The second overtone of an open pipe corresponds to the third harmonic, with a wavelength of 2L/3. Using the speed of sound and the pipe's length, we find the frequency, which is the same for the string. Solving for the speed of waves on the string gives approximately 120 m/s.

A String,0