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Guest Message by DevFuse

# where's the plane?

4 replies to this topic

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Posted 21 February 2013 - 09:23 AM

Michelle, john, and Kiru are all outside at the time a Jet is observed in the sky. Kiru hears the Jet's sonic boom two seconds before Michelle and seven seconds before John. if you were to draw a line to connect their locations they would form a triangle. Michelle is 10000 feet from Kiru. Kiru is 15000 ft from John. And John is 6000 ft from Michelle. Find a formula to derive the possible locations of where the sonic boom originated.

Spoiler for If it helps

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### #2 bonanova

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Posted 21 February 2013 - 08:09 PM

Are you taking into account that a sonic boom sweeps along the ground at the speed of the plane that generates it? Or are we to assume the sound originates from a fixed point and propagates at its native speed?

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
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### #3 Rob_Gandy

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Posted 21 February 2013 - 08:23 PM

No clue about how to come up with a formula, but I did draw it out.

Spoiler for If I'm not mistaken

Spoiler for Image

Spoiler for Explanation

I didn't really think about the height of the plane though....oops

Edited by Rob_Gandy, 21 February 2013 - 08:26 PM.

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### #4 k-man

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Posted 21 February 2013 - 09:28 PM   Best Answer

Spoiler for my take

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Posted 22 February 2013 - 03:31 AM

Are you taking into account that a sonic boom sweeps along the ground at the speed of the plane that generates it? Or are we to assume the sound originates from a fixed point and propagates at its native speed?

for the sake of simplicity and hopefully so i can actually declare a right answer, let's assume it originates from a fixed point.

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