A child has an ear canal that is 1.3cm long. At what sound frequencies in the audible range will the child have increased hearing sensitivity?

Answer 1

There will be enhanced sensitivity whenever the sound frequency corresponds to a fundamental or harmonic of an organ pipe with one open end and one closed end, 1.3 cm long. This will excite resonant oscillations within the ear

Answer 2

i appreciated your work... but how do i get answer in Hz.

Answer 3

There will be resonance whenever the 1.3 cm ear canal length equals an odd number of quarter wavelengths (1, 3, 5 etc.). For the fundamental resonant frequency, wavelength = 4x1.3 = 5.2 cm. Divide the sound speed (about 30,000 cm/s) by that wavelength for the frequency in Hz.

Check my thinking. I may have the fundamental resonant wavelength wrong.

Answer 4

I didn't quite follow ...