33.37 • BIO Heart Sonogram. Physicians use high-frequency(f = 1–5 MHz) sound waves, called ultrasound, to image internal or-gans. The speed of these ultrasound waves is 1480 m/s in muscle and344 m/s in air. We define the index of refraction of a material for soundwaves to be the ratio of the speed of sound in air to the speed of soundin the material. Snell's law then applies to the refraction of sound waves.(a) At what angle from the normal does an ultrasound beam enter theheart if it leaves the lungs at an angle of 9.73° from the normal to theheart wall? (Assume that the speed of sound in the lungs is 344 m/s.)(b) What is the critical angle for sound waves in air incident on muscle?

Given:- Physicians use high-frequency (f = 1 MHz to 5 MHz) sound waves, called ultrasound, to image…

Ives, image d of these ultrasound waves is 1480 m/s in We define the index of refraction of a mater ratio of the speed of sound in air to the spe Snell’s law then applies to the refraction of s gle from the normal does an ultrasound be: s the lungs at an angle of 9.73° from the n

Ives, image d of these ultrasound waves is 1480 m/s in We define the index of refraction of a mater ratio of the speed of sound in air to the spe Snell’s law then applies to the refraction of s gle from the normal does an ultrasound be: s the lungs at an angle of 9.73° from the n

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter3: Interference

Section: Chapter Questions

Problem 47P: To save money on making military aircraft invisible to radar, an inventor decides to coat them with...

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Can a sound wave in air be polarized? Explain.
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