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# Herr Professor Doctor Alex

## Question

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. 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.

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[1]

If you spin a hard boiled egg and briefly stop it, it will stay stopped. Do the same to a raw egg and the yolk will keep it going.

[2]

Do you mean (a) how does it compare to a round trip with no wind, or (b)how does each leg of the trip compare?

The wind adds a vector of +N as a tail wind and -N as a headwind. Assuming they are constant, (a) it will be the same length of time or (B) the leg with the tail wind will take the most time.

Thinking outside of the box -

1) The tailwind leg won't take any less time because the airline has a schedule to keep. They will just use less power and get there about the same time.

2) It would be really hard to have a constant headwind and tailwind on the same trip because airlines have different paths they take for round trips. If they didn't it would risk midair collisions.

3) If they are in North America, then the departure flight has the headwind and is leaving from the east. This will take MUCH longer because we all know east coast terminals are always late. :0)

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clarification.

compare the round-trip air travel times with and without a constant wind.

the pilot doesn't know about schedules - kind of like real life.

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What if the wind blew at the plane's air speed?

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[1] As several have said, spin the egg and stop it momentarily.

A raw egg's liquid insides are still spinning and when you let go the egg will spin again.

[2] No one got this right.

or you said the tailwind aids as much as the headwind hinders,

thus the trip will take the same time.

One said the tailwind slows you down, but I think that was a brain typo.

I recognize such things, because of my great familiarity with them.

Anyway, "same time" is incorrect..

While the tailwind increases your ground speed the same amount the headwind decreases it,

the two speeds [plane+wind] and [plane-wind] do not average to [plane]. Why not?

You don't compare speeds over similar distances to get average speed.

You compare speeds over similar times to get average speed.

As hinted, suppose the wind speed equaled the plane's air speed.

On the tailwind leg of the trip, the plane's ground speed would be doubled.

But on the headwind leg of the trip, the plane's ground speed would be zero.

It would then take forever to complete the trip.

The answer is: any constant wind - in any direction - will increase the duration of a round trip,

provided the plane maintains a constant air speed.

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You're working too hard on the egg puzzle. You don't need to stop the raw egg -- it will stop on its own while a hard boiled one just keeps spinning. When you try to spin a raw egg like a top the internal friction and the sloshing of the non-homogeneous contents prevents a good spin -- so you would have to work very, very hard to do the stop & start trick (maybe an electric drill with a suitable gripper would work). No problem spinning the hard-boiled egg, though. Try it.

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What if the wind blew at the plane's air speed?

then that would be some mighty fast winds, and not even the insane would fly then.

We should worry more on "zomg there is 400mph winds" and less on "jeez, will this trip take longer, I need to get home"

lol

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It was interesting to me that even in a cross wind, favoring neither leg, the trip takes longer.

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Spin the egg. A hardboiled egg will spin very fast and a fresh egg will not. Or wait for the Equinox; You can balance a fresh egg on its end.

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Even in a direct cross wind the pilot must turn into the wind in order to maintain the same path over the ground.

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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.

1.Too easy.

2.will increase the duration.The tailwind will increase the speed,but the headwind will decrease it much more.let's say the wind blows with the speed of the plane.In this case the tailwind will double the speed of the plane,but the headwind will stop the plane and the time needed from the plane to reach it's destination will be infinity.

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with the definition of a roundtrip being leave from one airport and the final destination being the same airport, compared to a still day the roundtrip with the headwind would take more time and the roundtrip with the tail wind would take less. This being true if you flew around the earth in one direction

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I get that there's a fancy-schmancy answer to this, but have you ever cooked with eggs? You can feel the difference quite clearly just by holding them and moving them around a little bit. You can feel the yolk sloshing around inside a raw egg, whereas a hardboiled egg feels totally solid.

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Spin the egg. A hardboiled egg will spin very fast and a fresh egg will not. Or wait for the Equinox; You can balance a fresh egg on its end.

Hardboiled eggs will spin much longer because the yolk isnt spinning on its own. as for the equinox, it has to be the spring equinox, thats when gravity will be just right to hold the yolk in the right spot. no other equinoxes will work

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with the definition of a roundtrip being leave from one airport and the final destination being the same airport, compared to a still day the roundtrip with the headwind would take more time and the roundtrip with the tail wind would take less. This being true if you flew around the earth in one direction

Roundtrip with headwind or roundtrip with tailwind isn't possible since you change direction.

The question meant to ask given that in a roundtrip you'll have say a headwind going and a tailwind returning, will that add time to the total trip?

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I get that there's a fancy-schmancy answer to this, but have you ever cooked with eggs? You can feel the difference quite clearly just by holding them and moving them around a little bit. You can feel the yolk sloshing around inside a raw egg, whereas a hardboiled egg feels totally solid.

You have it.

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Hardboiled eggs will spin much longer because the yolk isnt spinning on its own. as for the equinox, it has to be the spring equinox, thats when gravity will be just right to hold the yolk in the right spot. no other equinoxes will work

But I'm curious about the equinox thing. Do you have a reference link I could look at?

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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.

well if u spin the both eggs on the floor you can easily find out which one is raw and boiled.

And about the second question i am not very sure but i think it will take the same time.

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Spin the egg. A hardboiled egg will spin very fast and a fresh egg will not. Or wait for the Equinox; You can balance a fresh egg on its end.

That's a misconception. You can balance an egg at any time, not just on the equinox.

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well if u spin the both eggs on the floor you can easily find out which one is raw and boiled.

And about the second question i am not very sure but i think it will take the same time.

[1] Yes.

[2] Any wind, head/tail/side will lengthen a round trip.

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if the egg is truly raw, then a baby chick will eventually hatch.

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if the egg is truly raw, then a baby chick will eventually hatch.

If the egg was laid in flight with a tail wind then there shouldnt be much difference in air temperature affecting the egg, however if the egg was laid into a head wind then wind-chill factor may seriously reduce the eggs`chances of hatching, which wouldÂ´nt be a bad thing at 35000ft if the chick wasÂ´nt used to heights.

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Egg - spin is best solution as noted

Flight Explained - It is always longer.......

It may be thought that if an out-and-return trip is flown, where the wind is directly aligned with the required track, the headwind encountered in one direction will be offset by the tailwind in the reverse direction, and thus the total flight time will be equivalent to that in nil wind conditions. Not so, the greater the wind speed the greater the flight time on an out-and-return flight, no matter what the wind direction.

Imagine a flight Alphaâ€“Betaâ€“Alpha in nil wind conditions. The ground speed on both the outward and return legs would equal the TAS (75 kn) and each leg would take 120 minutes for a total flight time of 240 minutes. Now let's factor in a 25 knot north-east wind. The ground speed on the outward leg would be 50 kn and the ETI would be 180 minutes, whereas the ground speed on the return leg would be 100 kn and the ETI 90 minutes for a total flight time of 270 minutes.

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SPIN THE EGG ON IT'S SIDE, IF IT SPINS FAST IT IS COOKED, IF IT SPINS SLOW IT IS UNCOOKED.

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What if the wind blew at the plane's air speed?

NOT POSSIBLE.

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