Calculating Echo Time for Sound in Water and Air

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In summary: The sound travels the same distance in both the water and air, so the time it takes to travel that distance will be the same. Therefore, the additional time it takes for the echo in the air to return will also be 0.4 seconds, since it travels at a rate of 340 m/s. In summary, the boat is floating at rest in dense fog near a large cliff. The captain sounds a horn at water level and the sound travels through the salt water and the air (340 m/s) simultaneously. The echo in the water takes 0.4s to return, and the additional time it will take for the echo in the air to return is also 0.4 seconds.
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Homework Statement



A boat is floating at rest in dense fog near a large cliff. The captain sounds a horn at water level and the sound travels through the salt water and the air (340 m/s) simultaneously.

The echo in the water takes 0.4s to return. How much additional time will it take for the echo in the air to return?

Homework Equations



##v = \frac{Δd}{Δt}##

The Attempt at a Solution



So my take is that ##Δt = 0.4s## for the water echo and a quick look on wiki told me the speed of sound under salt water is ##v = 1560 m/s##.

This yields ##Δd = vΔt = 624m##.

So the salt water echo takes 0.4 seconds to travel a total distance of 624 m at a rate of 1560 m/s.

Now I'm asked to find how much additional time will it take for the echo in the air to return? So I'm being asked to find ##Δt## for the sound in the air.

I'm given that ##v = 340 m/s## in the air ( By the question ) so the pieces look like they're going to fall together.

I just need to confirm one thing, would i still use ##Δd = 624m## in this next calculation? If so why? If not, why not?

EDIT : I forgot to mention the reason I'm doing this is because I know when I subtract the time it took for the air echo to come back by the time it took for the salt water echo to come back I will get the difference the question is asking for.

EDIT 2 : Nevermind I was reading this question incorrectly. I got my answer.
 
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Zondrina said:
I just need to confirm one thing, would i still use ##Δd = 624m## in this next calculation? If so why? If not, why not?
Yes. This is simply the distance that the boat is from the cliff.
 

1. How is sound produced?

Sound is produced when an object vibrates, creating sound waves that travel through a medium, such as air, water, or solids. These waves are then detected by our ears and interpreted by our brains as sound.

2. What is the speed of sound?

The speed of sound varies depending on the medium it is traveling through, as well as temperature and humidity. In dry air at room temperature, sound travels at approximately 343 meters per second (767 miles per hour).

3. How does sound travel?

Sound travels in waves, which are longitudinal compressions and rarefactions of the medium it is traveling through. This means that the molecules of the medium vibrate back and forth in the same direction of the sound wave.

4. Can sound travel through a vacuum?

No, sound cannot travel through a vacuum because there is no medium for the sound waves to travel through. Sound waves require molecules to vibrate in order to propagate.

5. What is the difference between pitch and volume?

Pitch refers to the frequency of a sound, or how many cycles of a sound wave occur per second. A high pitch sound has a higher frequency, while a low pitch sound has a lower frequency. Volume, on the other hand, refers to the amplitude or intensity of a sound wave. A louder sound has a higher volume, while a softer sound has a lower volume.

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