SOLUTION: 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) simultaneous

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Question 1073701: 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 0.40 seconds to return. How much additional time will it take the echo in the air to return?

My solution: first find distance the boat is away from cliff

V = d/t

d = vt

speed of sound in salt water (according to text book) is 1470 m/s.

therefore d = (1470 m/s) (0.40s)
d= 588 meters.

Now 588/2 = 294m divide by 2 because sound travels to cliff then reflects back an equal distance

Now find the time in air

t= d/v
t= 294m/340 m/s
t= 0.86 seconds.

Finally, how much additional time in the air?

0.86 seconds - 0.40 seconds = 0.46 seconds.

Am I correct?
Answer by ikleyn(52884) About Me  (Show Source):
You can put this solution on YOUR website!
.
In your solution you didn't account that the sound wave in the air must go forward AND then return back.