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Herr Professor Doctor Alex


bonanova
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He's doing what? asked Jamie.

Shh.. here he comes, answered Ian. He's studying physics

on the Internet. I think we should humor him, OK?

So here's yer challenges for tonight, me boys. Alex had a

strange way of smiling when he thought he had his friends

over a barrel. He was smiling now.

[1] how can you tell a raw egg from a hard-boiled egg?

[you can't break the shell or use light, heat, sound or X-rays]

[2] compared to a still day, will a round-trip airplane ride take more,

less or equal time if there's a constant wind blowing?

[a headwind one way, a tailwind the other way]

And there's more where that came from, boys ;) ... have fun.

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All of you are messed up on the airplane one. Realizing of course that it is not really an airplane we are talking about here but assuming it is.

An airplane needs a HEADWIND to be able to fly. So if you had a tail wind greater than or equal to the airplane's attempted speed, it would not fly. With a tail wind the pilot might actually have to ramp up the ground speed to keep actually flying.

Of course a head wind can be strong enough to wipe out the forward groundspeed.

No this is an incorect statement, Aircraft fly with a tailwind all the time. It just means they rotate (take off) at a higher ground speed., however they always take off into wind so this is irevelant

Edited by taliesin
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He's doing what? asked Jamie.

Shh.. here he comes, answered Ian. He's studying physics

on the Internet. I think we should humor him, OK?

So here's yer challenges for tonight, me boys. Alex had a

strange way of smiling when he thought he had his friends

over a barrel. He was smiling now.

[1] how can you tell a raw egg from a hard-boiled egg?

[you can't break the shell or use light, heat, sound or X-rays]

[2] compared to a still day, will a round-trip airplane ride take more,

less or equal time if there's a constant wind blowing?

[a headwind one way, a tailwind the other way]

And there's more where that came from, boys ;) ... have fun.

Answer to Numero Uno: You put the egg in boiling water. That way, no mater what it used to be, you know that now it's a hard boiled egg.

Answer to Numero Dos: Who cares, the length of time you wait in the plane is a blink of an eye compared to the hours you wait in the airport

(security checks, flight delays, etc.)

Edited by Marinja
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Answer to Numero Uno: You put the egg in boiling water. That way, no mater what it used to be, you know that now it's a hard boiled egg.

Answer to Numero Dos: Who cares, the length of time you wait in the plane is a blink of an eye compared to the hours you wait in the airport

(security checks, flight delays, etc.)

What if the wind speed was the same as the plane's air speed?

Are you sure the headwind leg would take only a blink of an eye?

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1) I had never heard of the spinning trick. I was just going to suggest shaking it. Even if you couldn't hear any sloshing, you could probably feel the liquid moving around.

2) I read through a lot of the answers and I didn't see any that were really straight to the point. The wind is slower. To test that, just do a simple calculation.

Say the trip is 1000mi total (500mi each way). With no wind, you travel 500mph, and it takes 2hrs.

With wind, you travel 500mi at 400mph (1hr15min), and 500mi at 600mph (50min). Therefore, with wind is 2hr5min, 5min longer than with no wind.

He's doing what? asked Jamie.

Shh.. here he comes, answered Ian. He's studying physics

on the Internet. I think we should humor him, OK?

So here's yer challenges for tonight, me boys. Alex had a

strange way of smiling when he thought he had his friends

over a barrel. He was smiling now.

[1] how can you tell a raw egg from a hard-boiled egg?

[you can't break the shell or use light, heat, sound or X-rays]

[2] compared to a still day, will a round-trip airplane ride take more,

less or equal time if there's a constant wind blowing?

[a headwind one way, a tailwind the other way]

And there's more where that came from, boys ;) ... have fun.

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1) I had never heard of the spinning trick. I was just going to suggest shaking it. Even if you couldn't hear any sloshing, you could probably feel the liquid moving around.

2) I read through a lot of the answers and I didn't see any that were really straight to the point. The wind is slower. To test that, just do a simple calculation.

Say the trip is 1000mi total (500mi each way). With no wind, you travel 500mph, and it takes 2hrs.

With wind, you travel 500mi at 400mph (1hr15min), and 500mi at 600mph (50min). Therefore, with wind is 2hr5min, 5min longer than with no wind.

Correct on both. ;)

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I didn't read everything. But,...

Wind doesn't have anything to do with the speed or time of a flight. If there is a headwind, you increase throttle to maintain speed. Tailwind, decrease throttle. FAA regulates speed, not nature.

:P
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I didn't read everything. But,...

Wind doesn't have anything to do with the speed or time of a flight. If there is a headwind, you increase throttle to maintain speed. Tailwind, decrease throttle. FAA regulates speed, not nature.

:P

What if the headwind equaled the plane's maximum airspeed? ;)

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Just thought I'd throw this out. If, in fact, the tailwind is equal to the plane's speed, then the plane can't fly due to no pressure differential over the wing; so there's no lift.

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After checking my refrigerator I found that a hard boiled egg is heavier than a raw egg.

As for the airplane, the head wind would show the plane down but the tail wind would help speed up it's progress, therefore canceling each other out. Under these particular conditions there would be virtually no diference in the travel time of the airplane. It is so cool to have had a father who was an aerospace engineer. Thanks Pop.

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the head wind would show the plane down but the tail wind would help speed up it's progress, therefore canceling each other out. Under these particular conditions there would be virtually no diference in the travel time of the airplane.

Hi kat, and welcome to the Den. B))

Would the travel time be affected at all if the head wind equaled the plane's air speed?

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Re the plane: The best intuitive explanation that I've heard is...

While the headwind and tailwind change the groundspeed in equal but opposite directions, the plane fights against the headwind *for a longer period of time*. Thus the average ground speed must decrease.

My understanding is that this principle accounted for the basis of the Michelson-Morley experiment, where the researchers were testing for the existence of "ether wind." Their experiment would be pointless if headwinds and tailwinds canceled each other out.

http://en.wikipedia.org/wiki/Michelson-Morley_experiment

-Alan

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Re the plane: The best intuitive explanation that I've heard is...

While the headwind and tailwind change the groundspeed in equal but opposite directions, the plane fights against the headwind *for a longer period of time*. Thus the average ground speed must decrease.

My understanding is that this principle accounted for the basis of the Michelson-Morley experiment, where the researchers were testing for the existence of "ether wind." Their experiment would be pointless if headwinds and tailwinds canceled each other out.

http://en.wikipedia.org/wiki/Michelson-Morley_experiment

-Alan

That's a great observation.

Thanks.

- bn

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1. spin the egg, and stop it in mid-spin. Let go, if it continues spinning it is raw, if it is still stopped it is hardboiled

2. assuming the question is asking if it will take longer going or returning for a round trip plane ride with a constant wind AND assuming you don't have to circle back around the airports to land, AND assuming you are going only fast enough to be airborne I think you will go faster with a tailwind behind you because you have to travel even faster to get the proper wind speed over the wings. However, if you travel at 600knots each way, well enough velocity to be airborne, it doesn't really matter and will take the same amount of time each way.

Actually, for #1, it's impossible. I tried it, but I cheated to make it work. Since most people go all smart-a** on these questions, then here:

You cannot use the "continues spinning" because how would you know? If you could use no light, then you couldn't see it continue. If you could use no sound, you couldn't hear it continue spinning.

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Actually, for #1, it's impossible. I tried it, but I cheated to make it work. Since most people go all smart-a** on these questions, then here:

You cannot use the "continues spinning" because how would you know? If you could use no light, then you couldn't see it continue. If you could use no sound, you couldn't hear it continue spinning.

Hi Dupie,

Great observation.

What the OP should have done, to be more precise, is to prohibit the use of transmitted light, to observe the interior of the egg.

Using reflected light, one can observe the exterior of the egg and see whether is spins or not.

But if you like, you could touch the egg, lightly, with your fingertips to sense continued spinning.

[Did someone here mention being smart-a**?] B))

Welcome to the Den!

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Well as far as the plane goes it will take just as much time wind or no wind. 400mph is 400mph no matter what the wind is doing. The real question should read compared to a still day, will a round-trip airplane ride take more, less or equal "FUEL" if there's a constant wind blowing? Unless the plane is traveling at full throttle both ways and cannot compensate for the head wind. And I am sure that it would depend on the plane as to whether or not it will take more fuel!

As far as the egg yes it would be much harder to spin a raw egg than a hard boiled!

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Well as far as the plane goes it will take just as much time wind or no wind. 400mph is 400mph no matter what the wind is doing. The real question should read compared to a still day, will a round-trip airplane ride take more, less or equal "FUEL" if there's a constant wind blowing? Unless the plane is traveling at full throttle both ways and cannot compensate for the head wind. And I am sure that it would depend on the plane as to whether or not it will take more fuel!

As far as the egg yes it would be much harder to spin a raw egg than a hard boiled!

Not quite. We're not talking about the speed of the plane. Nor are we talking about fuel. We're talking about time.

[2] compared to a still day, will a round-trip airplane ride take more,

less or equal time if there's a constant wind blowing?

For the egg, would it be harder? Would a greater amount of force have to be applied to spin a raw egg than a hard boiled? Uh... gotta go look at some fluid dynamics to figure that one out.

*looks to the clock* Crap, all I have time for is cynicism and sarcasm. Be back with science and math later.

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Since neither its volume nor weight changes, how do you explain a change in density? ;)

Actually, whether or not ugoindown is correct, The outer shell of a chicken egg is actually a semipermeable membrane which allows some matter to pass through,

Thus there is a possibility for the mass of the egg to change. ;)

Although, I'm not entirely sure how the new density would compare to the density of water.

Edited by Romulus064
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