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help with college math word prob?
An echo is an relection of sound off an object. A perosn travels to hocking hills to enjoy the acoustics of the natural rock formations. She stands in ash cave and yells. If she hears an echo .25 seconds later, how far away is the cave wall? Wave speed is 345 m/s.
Public Comments
- You know that she hears it in .25 second. What is .25 of 345? 86.25. She is 86.25 meters away back and forth from cave wall. Divide by 2 because its BACK AND FORTH so 42.125 or 4 (1/8)
- if the wave travels 345 meters in one second and you hear your echo in one-fourth of a second then the distance must be less than 345 meters... there's your clue
- = (345 m/s[0.25 sec])/2
= 86.25 m/2
= 43.125 or 43 1/8 m
Answer: 43.125 meters
The voice went then it came. It means the distance traveled is 86.25 meters but this distance trip is round trip.
