79. A human ear detects sound as a result of fluctuations in air pressure against the eardrum, which are in turn transmitted into nerve impulses that the brain translates as sound. Suppose that the pressure P(t) of a sound wave on a person's eardrum from a source 20 ft away is given by P(t) = 0.02 cos (1000t – 107). In this model P(t) is in pounds per square foot and t is the time in seconds after the sound begins. Simplify the right side by applying the difference formula for cosine.

79. A human ear detects sound as a result of fluctuations in air pressure against the eardrum, which are in turn transmitted into nerve impulses that the brain translates as sound. Suppose that the pressure P(t) of a sound wave on a person's eardrum from a source 20 ft away is given by P(t) = 0.02 cos (1000t – 107). In this model P(t) is in pounds per square foot and t is the time in seconds after the sound begins. Simplify the right side by applying the difference formula for cosine.

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter17: Sound Waves

Section: Chapter Questions

Problem 17.20P: The area of a typical eardrum is about 5.00 X 10-5 m2. (a) (Calculate the average sound power...

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