Question

Sound enters the ear, travels through the auditory canal, and reaches the eardrum. The auditory canal is approximately a tube open at only one end. The other end is closed by the eardrum. A typical length for the auditory canal in an adult is about 2.6 cm. If the speed of sound is 338 m/s. What is the fundamental frequency of the canal? (Interestingly, the fundamental frequency is in the frequency range where human hearing is most sensitive.)

Answer 1

Assume it is 1/4 lambda, closed at one end.

1/4 lambda= .025m
lambda= .1m
f= 338/.1= 3380hz.

Answer 2

f1=c/(4L)

c=338m/s
L=2.6cm=0.026m

f1=338/(4x0.026)
=3250Hz