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Can anyone give me a quick link?

Thanks!

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- Thread starter mbrmbrg
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- #1

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Can anyone give me a quick link?

Thanks!

- #2

rcgldr

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- #3

Danger

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It might be famous in the US, but I've sure never heard of it. What the hell are you talking about?

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HallsofIvy

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The

What makes it "famous" is that there is a story that a person once asked (Von Neumann, Weyl, Wiener, ... pick your favorite big brain) that question. The mathematician thought for a second and gave the correct answer. The first person chuckled and said "many people try to do it by summing an infinite series." At which (Von Neumann, Weyl, Wiener, ... ) looked puzzled and said "but I did it by summing an infinite series!"

- #5

Danger

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Okay, I see what the original problem was. Does the question assume a constant speed for the bird with zero turn-around time, or are positive and negative accelerations included?

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Jeff Reid said:

:hits self over head repeatedly:

Right... Talk about a brain twister. I knew there was an easy solution and I thought for SO LONG, and yet--

Well, thanks for untwisting my brain!

- #7

nrqed

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It does indeed assume zero turn-around time and constant speed throughout (and no wind ) which is why it can be done by just calculating he time until collision and multiplying this by the speed of teh bird.Danger said:

Okay, I see what the original problem was. Does the question assume a constant speed for the bird with zero turn-around time, or are positive and negative accelerations included?

- #8

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Two trains, each having a speed of 25 km/h, are headed at each other on the same straight track. A bird that can fly 60 km/h flies off the front of one train when they are 58 km apart and heads directly for the other train. On reaching the other train it flies directly back to the first train, and so forth. (We have no idea why a bird would behave in this way.) What is the total distance the bird travels before the trains collide?

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Danger

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Not the most efficient way to play badminton, but I suppose it would be good for a laugh.mbrmbrg said:A bird that can fly 60 km/h flies off the front of one train when they are 58 km apart and heads directly for the other train. On reaching the other train it flies directly back to the first train, and so forth.

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