Calculating Distance with Sound Waves

AI Thread Summary
An instant camera calculates distance by emitting a sound wave and measuring the time for the echo to return. For a subject 3.00 meters away, the sound wave takes approximately 8.75 milliseconds to return. The total distance the sound travels is 6 meters, as it goes to the subject and back. The discussion clarifies that while the one-way distance is 3 meters, the round trip doubles that distance. Understanding this concept is crucial for accurate distance measurement using sound waves.
whitehorsey
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1. A certain instant camera determines the distance to the subject by sending out a sound wave and measuring the time needed for the echo to return to the camera. How long would it take the sound wave to return to the camera if the subject were 3.00 m away?


2. d = vt



3. d = vt
3 = 343t
t = 8.75 x 10^-3 sec

im not sure if this is correct.
 
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How far is the sound actually traveling in total? Is it really just 3m?
 


danago said:
How far is the sound actually traveling in total? Is it really just 3m?

yep its just 3m
 


It travels 3m getting there, but what about the trip back to the camera? Its got to travel another 3m, for a total of 6m.
 


oh i see thank you! :]
 

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