Let's say that a loud pulse is emitted from a point on the surface of the Earth in all directions. Who would hear the sound first, someone located one km away horizontally, or someone located on a mountain top one km above the location of the sound source? Note that air is cooler at higher elevations.
1.the person located one km away horizontally
2.the person located one km away vertically
3.They would both hear the sound at the same instant.
4.There is not enough information available to determine this.
Question 2
If the wavelength of sound is increased by a factor of 3, what happens to its speed and frequency?
1.Its speed increases by a factor of 3, and so does its frequency.
2.Its frequency increases by a factor of 3, but the speed stays the same.
3.Its frequency decreases by a factor of 3, but its speed stays the same.
4.Its speed decreases by a factor of 3, and so does its frequency.
Summation of Heart Sounds, Loud S1
Carotid pulse.
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Ulysses S. Grant poses at City Point, Virginia, during the siege of Petersburg.
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