A gun is fired 2.0 km away from a mountain. The sound of the shot travels at 340 m/s?

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shiftcomma3

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How long will it take the person who fired the gun to hear the echo?

Please try and show your work! I'm trying to understand this, not just get the answer! Thanks :)
 
Since the mountain is 2 km away, the sound must travel to the mountain and reflect back, which means that the sound in total travels 4 km. Since time = distance/ velocity, and we just found the distance and the velocity is given, we can find the time
t = 4 km / 340 m/s, First convert km to m (multiply by 1000)
t = 4000 m / 340 m/s
t ≈ 1.176 seconds
 
diatance = 2 km= 2000 m ( because ur units are in S.I. system)

time = distance/speed
time = 2000 x 2/340 (as it has to travel back so 2times distance u have to consider)
time= 11.764 s
 
Since the mountain is 2 km away, the sound must travel to the mountain and reflect back, which means that the sound in total travels 4 km. Since time = distance/ velocity, and we just found the distance and the velocity is given, we can find the time
t = 4 km / 340 m/s, First convert km to m (multiply by 1000)
t = 4000 m / 340 m/s
t ≈ 1.176 seconds
 
Ok if you want to get technical about this remember that the sound will bounce from all locations around you and will return with the closest distance to you the fastest. SO if you are 340 meters away from the nearest wall that sound will return to you in 2 seconds, it will take it 1 second to get there and one to come back. However getting more technical there is interference from the other sounds returning that needs to be accounted for but that is a different calculation all together. I do mentioned it because it does get more complicated to calculate but it gives you a clearer picture of what is going on. So if the nearest wall is less than the distance lest say 150m then the person will hear the sound 150m divided by 340m/s that will give you .4412 seconds X 2 because it needs to get there and come back. If the wall is 900m then if you divide it by 340m/s you will get 2.65seconds but that is only getting there to come back you must multiply by two. So your formula is ECHO = DISTANCE divided by the SPEED OF SOUND x 2 remember that this is for these particular question. It is also assuming that the sound travels at that speed in air, and various other things but as long as you get this you will be able to seek further. GOOD LUCK..........by the way there is also an echo that comes from the ground, but that is neglected on this question as they want yo to get an understanding of speed of sound.
 
Ok if you want to get technical about this remember that the sound will bounce from all locations around you and will return with the closest distance to you the fastest. SO if you are 340 meters away from the nearest wall that sound will return to you in 2 seconds, it will take it 1 second to get there and one to come back. However getting more technical there is interference from the other sounds returning that needs to be accounted for but that is a different calculation all together. I do mentioned it because it does get more complicated to calculate but it gives you a clearer picture of what is going on. So if the nearest wall is less than the distance lest say 150m then the person will hear the sound 150m divided by 340m/s that will give you .4412 seconds X 2 because it needs to get there and come back. If the wall is 900m then if you divide it by 340m/s you will get 2.65seconds but that is only getting there to come back you must multiply by two. So your formula is ECHO = DISTANCE divided by the SPEED OF SOUND x 2 remember that this is for these particular question. It is also assuming that the sound travels at that speed in air, and various other things but as long as you get this you will be able to seek further. GOOD LUCK..........by the way there is also an echo that comes from the ground, but that is neglected on this question as they want yo to get an understanding of speed of sound.
 
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