In: Physics
READING 2 The eardrum is displaced surprisingly little when a sound wave strikes it. Some idea of the displacement of the eardrum by a sound wave can be obtained by using Equation 7.1: Equation for wave energy The displacement amplitude, A, of the air molecules gives us a lower limit to the displacement of the eardrum.
At the threshold of hearing at 3.4 kHz, the sound intensity is about 10−12W/m2. The threshold of pain begins at an intensity of 1.0W/m2 (19).
What is the amplitude of eardrum vibrations at these intensities?
The density of air is 1.3kg/m3. The speed of sound is 331m/s.
Please write your answers with one decimal places.
(________________10^−3 nm (at threshold of hearing) (This value is ~ 3/100 the diameter of a hydrogen atom!)
________________10^3 nm (at threshold of pain)
I believe the answer to the first question is 3.19 x to^-3 nm