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SpicyWassabi101
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Homework Statement
A boat is floating at rest in dense fog near a cliff. The captain sounds a horn at water level and the sound travels through the salt water (1470 m/s) and the air (340 m/s) simultaneously. The echo in the water takes 0.40s to return. How much additional time will it take the echo in the air to return?
Homework Equations
v = Δd/Δt
The Attempt at a Solution
First Attempt:
v = Δd/Δt
Δd = v Δt = (1470 m/s) (0.40 s) = 588 m
Δt = Δd/v = 588m / 340 m/s = 1.73 s
Δt = 1.73 s – 0.40 s = 1.33 s
The echo in the air took 1.33 s longer to return.
Second Attempt:
I was thinking that 1.73 s would be the total time, so then I would have to divide 1.73 s by 2 to get the return time (0.865 s). Then I would subtract 0.40s from 0.865 s to get the additional time it took the echo to return, which would be 0.465 s. Like this:
v = Δd/Δt
Find total time:
Δd = v Δt = (1470 m/s) (0.40 s) = 588 m
Δt = Δd/v = 588m / 340 m/s = 1.73 s
Then find return time:
1.73 s/2 = 0.865 s
Then find additional time:
0.865 s - 0.40s = 0.465 s
The echo in the air took 0.465 s longer to return.
Please help me figure out which process is correct, if they even are correct :)
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