How Long After a Crash Does Sound Reach Different Observers?

AI Thread Summary
The discussion centers on calculating the time it takes for sound from a crash to reach two observers: one underwater and one on the dock. Given the speed of sound in water is 1450 m/s and in air is 346 m/s, the time difference can be determined using the formula t = d/v. The problem does not specify the distance to the crash, but it emphasizes the need to understand the relative speeds of sound in different mediums. Ultimately, the solution hinges on establishing the ratio of sound travel times for both observers.
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Homework Statement



the air temperature is 20 degree celcius. you are swimming underwater when you hear a boat noise. then 305s later, you hear a crash. if the speed of sound in wter is 1450m/s, how long after the crash does your friend on the dock beside oyu hear the crash?

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The Attempt at a Solution



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Do you know the speed of sound in air?
 
346m/s?
 
Ok so you know the time it takes for the sound to transverse a distance in a certain medium is t = \frac{d}{{v_{medium} }}. You really don't know the "distance" because it's not actually stated in the problem that the crash occurred immediately after the boat sound is heard but you CAN determine the ratio of the time sound waves take to reach each person using the equation.
 

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