# Naked Science Forum

## General Science => General Science => Topic started by: mawea on 07/11/2003 16:23:27

Title: Which way faster, east or west ?
Post by: mawea on 07/11/2003 16:23:27
hello einsteins,

i have a question which has been bugging me for years, hope you guys can help me figure this one out.
say points A , B , C are on common latitude. A is west of B and C is east of B. distance from A to B equals B to C.
if 2 planes take off ( travelling on same speed) from B , one heading west to A the other heads east to C, which one will arrive at their respective destination first? assume there is no wind.

remember earth rotates from west to east ? do you guys think it would be faster to travel westward to A ?

Title: Re: Which way faster, east or west ?
Post by: Pappy on 07/11/2003 18:20:21
Traveling at same "ground speed" there is no difference. However, since the Jet stream flows from West to East, planes travel faster heading east than when heading west, against the jet stream. In oder for the earth's rotation (I'm just speculating here so feel free to help me out) to affect this scenario, the plane would have to be outside the effects of gravity.........???
Title: Re: Which way faster, east or west ?
Post by: mawea on 08/11/2003 06:01:11
Thanks Pappy, I believe ground speed is affected by wind also. In this case let us assume there is no wind, and maybe i should rephrase myself, plane heading to A travels with velocity V and the other plane travels velocity -V in nil wind, just incase some of you may have some confusion..forgive my english as it isnt my 1st language. Could you (or anyone) please elaborate on the possible effects of gravity in this case? I think both planes are subject to the same gravitational effects , I may be wrong though.
Title: Re: Which way faster, east or west ?
Post by: Ians Daddy on 08/11/2003 06:06:05
If you threw a ball from a moving car, it would travel with the car for a bit before gravity pulled it down....momentum.
If you pulled the chair out from under someone as they were sitting down, they would miss the chair and bust their a\$\$....deviance.

Now, my belief is that traveling westward would be faster. There's not enough momentum from the rotation of the earth to make a difference either way. However, the earth would move enough that a certain point (chair) would be moved from under the plane (a\$\$). So, I would speculate that west would be faster. (Not counting time changes)
But, my mind is now debating with itself. Great. I know it doesn't take much, but now I'm confused. Thanks alot!

Welcome to the forum, Mawea.
Title: Re: Which way faster, east or west ?
Post by: mawea on 08/11/2003 16:09:13
I think the momentum or inertia explanation is probably correct.
Title: Re: Which way faster, east or west ?
Post by: Donnah on 08/11/2003 18:27:07
Provided you are not factoring time zones or jet stream in the question, I think that the plane would land at A slightly ahead of C due to the earth's westerly rotation.
Title: Re: Which way faster, east or west ?
Post by: tweener on 09/11/2003 03:07:26
I think the key to this question is what velocity are you measuring?  If you are measuring velocity relative to the surface of the earth and assuming no effect from wind, then there will be no difference going west or east, because the rotation of the earth cancels out of the equations.

On the other hand, if you are measuring velocity relative to the center of the earth (as all spacecraft orbital calculations must, but aircraft do not) then the rotation of the earth will make a significant difference.  The linear speed of the surface of the earth due to the rotation is approximately 1,000 miles per hour at the equator, diminishing to zero at the poles.  This speed would be added to the eastbound plane and subtracted from the westbound plane, thus making a big difference in the "velocity".   However, since the starting point is moving along with the end points of both planes, the speed change still cancels out and they will both arrive at the same time relative to their departure.

I think I just canceled everything out!

----
John
Title: Re: Which way faster, east or west ?
Post by: UScaV on 11/11/2003 00:06:00
I thought it didn't have anything to do with the rotation of the earth, but just the jet stream and the speed of it.  Not really sure why though, just what I was taught in class...
Title: Re: Which way faster, east or west ?
Post by: tweener on 11/11/2003 22:11:19
Actually, it doesn't have anything to do with the rotation of the earth because the atmosphere is rotating with the earth and the starting point of the "race" is rotating with the earth.  I didn't explain very well.

----
John
Title: Re: Which way faster, east or west ?
Post by: jojo on 15/11/2003 10:39:37
if the earth were to rotate extreemly fast.. and i was to jump.. could i land in a different country? (assuming i didnt get hit by houses or anything..) :D.. hehe stupid question.. but jst wondering.. :)
Title: Re: Which way faster, east or west ?
Post by: qpan on 16/11/2003 13:20:18
If you take the wind relative to the earth's surface as being zero, then the relative velocity of the plane in ANY direction is the same, as it starts off travelling at the same speed as the Earth's surface. This is because at the start of the journey, when the plane is stationary, it is travelling at the same speed as the Earth's surface, therefore allowing you to negate the effect of the rotation of the Earth (Vel Plane = Vel Earth => vel plane rel earth = 0). Therefore, you can now take the Earth as not rotating as the realtive velocity is equal to zero at the beginning.
However, in real life, the wind relative to the earth's surface is not zero as the atmosphere generally rotates at a slower speed than the earth's surface and so, therefore, it will have to travel against the atmosphere in one direction and with the atmosphere in the other direction, and obviously it goes slower when travelling against the atmosphere.

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: chris on 18/11/2003 18:19:47
So is the proposed plan for future air travel involving hopping up into near-space, sitting there a little while as the earth turns beneath you, and then landing in the right place, at all feasible ?

Chris

"I never forget a face, but in your case I'll make an exception"
- Groucho Marx
Title: Re: Which way faster, east or west ?
Post by: roberth on 18/11/2003 22:13:01
I would guess it is feasible. The only problem would be the force required to break from the gravitational pull of the earth. I believe you need to be going at about 25,000 kms/hour, which is faster than most commercial aeroplanes can go these days. Then, of course, it would get warm coming back in.
Title: Re: Which way faster, east or west ?
Post by: GlacierBlue on 26/11/2003 22:34:57
Your original question was concerning which of the two planes would reach their destination first. The idea of "First" is strange and may be a bit more complicated than you originally thought. Take for instance an expierement done by the USAF in the 1960's. They took 3 ceasium isotope clocks that measure time in the billionths (nano-second). They left one on the ground and loaded the other two into identical fighter jets. Plane A headed due East, while plane B headed due West. The planes (after several refuelings) circumnavigated the globe and landed at the airforce base from whence the came.

When the clocks where compared, (several times over the last few years) it was discovered to no ones great surprise that the plane that had traveled East (against the rotation of the Earth?) had experienced several thousandths of a second LESS TIME than the plane traveling West. The clock left on the ground at the AFB confirmed that it wasn't an anomaly or error.

While this isn't news to many people, Einstein predicted the outcome of this experiment when he wrote the General Theory of Relativity. Time, he said was effected by the speed at which any object traveled. So, while this might only serve to confuse the issue of who gets there first, plane A or B, at the very least it makes for some interesting conversation. :-)

If the multi-verse is a real construct then in some universe Im your God.
Title: Re: Which way faster, east or west ?
Post by: chris on 27/11/2003 00:18:45
What about the plane going west ?

Welcome to the forum by the way !

chris

"I never forget a face, but in your case I'll make an exception"
- Groucho Marx
Title: Re: Which way faster, east or west ?
Post by: GlacierBlue on 27/11/2003 23:50:06
Good question Chris. I don't remember what the effects were on that plane. Lets puzzle it out. If you live through less time the faster you go, then it makes sense that you would live through more time the slower you go. So if you could slow down in relation to the people around you, it would look like they were in >> fast forward.

What is the theoretical limit of this assumption?

We can assume then that speed is a factor of the energy inherent in an object. When scientists try to cool an object down to absoloute zero (zero kelvin) they are trying to get molecular activity to cease. Maybe one of the reasons that they havn't been able to achieve zero Kelvin rests on the fact that in relation to the universe everything within it has some amount of velocity.

It would be intersting to experience temperatures near zero Kelvin just to see if the slowing of molecular activity increased the amount of time that you lived through.

At zero Kelvin however a persons atomic structure would age in relation to its decreased speed. The person would not "freeze" but rather disolve as the component building blocks of their atomic structure aged to death in "no time" in relation to the outside world.

If the multi-verse is a real construct then in some universe Im your God.
Title: Re: Which way faster, east or west ?
Post by: qpan on 04/12/2003 12:25:53
One of the reasons that scientists cannot reach absolute zero is due to quantum fluctuations. Another other reason is that in order to cool something very close to absolute zero to absolute zero, you still need a temperature gradient, and so, your temperature can only approach absolute zero as an aymptote as you cannot create the temperature gradient by having the surroundings at lower temperature than absolute zero.
Also, velocity is relative, so particles travelling at the speed of light can still be at zero kelvin as long as they have no relative velocities to each other (as it is equally valid for the particles to suggest that they are stationary and everything else is travelling at the speed of light towards them).
Also, at zero kelvin, the person's body would degrade not due to ageing infinately fast due to travelling at zero speed, but due to the electrons falling into the nucleus destroying all chemical bonds. The person would not age faster as particles in frozen foods move slower than particles in fresh foods but frozen foods don't decompose quicker!

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: george on 04/12/2003 13:54:08
Errr I understood the top bit really well - thanks.

But I'm lost on this : "Also, at zero kelvin, the person's body would degrade not due to ageing infinately fast due to travelling at zero speed, but due to the electrons falling into the nucleus destroying all chemical bonds. The person would not age faster as particles in frozen foods move slower than particles in fresh foods but frozen foods don't decompose quicker!"

Can you clarify it a bit !
Title: Re: Which way faster, east or west ?
Post by: qpan on 04/12/2003 22:22:20
Yep- ok i'll try to clarify. As you all know, the body is made up of many chemical compounds. The only reason chemical compounds exist is so that the elements can share/donate/receive electrons to become more stable. However, at 0K, not even the electrons have any microscopic k.e. and so, fall into the positive nucleus (consider a planet in orbit- if it suddenly lost its speed, it would fall into the sun). Therefore, chemical bonds would break up due to the absence of electrons in their shells.
Also, to clarify further- protons take 10^32 years to decompose(theoretically- although none have been observed)- so the only way a body would decompose instantaneously due to decomposition of electrons is if the surroundings are travelling at near the speed of light- it is simply not sufficient to say that decomposition would happen instantaneously if the the microscopic KE is to equal zero. Also- ageing is different to decomposition- ageing is caused by oxygen free radicals released through respiration and decomposition is caused by the breaking up of compounds or subatomic particles (e.g. a proton)

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: qpan on 05/12/2003 14:28:53
oops- in post above should be:
...........decompose instantaneously due to decomposition of Protons is if the surroundings are...........

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: Quantumcat on 05/12/2003 14:46:03
You can edit you posts by clicking on the little button that looks like a notepad and pencil

Am I dead? Am I alive? I'm both!
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.stupid-boy.com%2Fsmilies%2Fkao%2Fotn%2Fcat.gif&hash=e4b91a72c020cc1c5d28487fff5428f1)
Title: Re: Which way faster, east or west ?
Post by: tweener on 06/12/2003 04:52:23
I don't think that electrons would fall into the nucleus even at 0 K.  I think the "lack of motion" only applies to the atoms and molecules, not the particles that make them up.  If the electrons stoppped, wouldn't they violate the wave equation and the uncertainty priniple?

----
John
Title: Re: Which way faster, east or west ?
Post by: qpan on 06/12/2003 12:55:02
Well- if the electrons did not fall into the nucleus, the substance would not be at 0 K would it? If the electrons still have ke, would this not mean that the atom still had ke? The movement of a negative charge would surely incite movement in a positive charge as it would lose/ gain p.e.? This effect would certainly cause the temperature of the substance to rise as fluctuations in the positions of the electrons would incite the movement of all positive nuclei in the substance (please correct me if i am wrong!)

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: qpan on 06/12/2003 13:04:13
actually- also read this forum here:
- it does make sense as i suppose the electrons cannot fall into the nucleus as it is one of the reasons absolute zero is not attainable (violation of heisenberg's law of uncertainty). Also, as i said earlier, you would not be able to cool something to absolute zero due to requiring an energy gradient (so it also violates the law of thermodynamics).
----So our debate is purely theoretical but about something which is actually theoretically impossible!--------

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: tweener on 07/12/2003 05:18:58
I read the forum thread and I still don't see anyone saying that the electrons will fall into the nucleus, or that the atoms will decay in any way.  I think the one post mentioned different definitions of temperature, and that may be the crux of the matter - what does absolute zero really mean.

I certainly don't know.

----
John
Title: Re: Which way faster, east or west ?
Post by: qpan on 07/12/2003 12:11:22
Hi tweener- i suppose this post from the forum is similar, although it says lowest electron orbital instead of electrons falling into nucleus, but then continues to go on about zero subatomic particle motion:
"Theoretically,

At Absolute zero all electronic motion ceases. All of the electrons in the atom will be in the lowest possible orbitals.

Zero motion of a subatomic particle violates Heisenberg Uncertainty Principle, so it is not possible to achieve this state."
So i suppose it wouldn't be possible for electrons to fall into the nucleus then! But if absolute zero is defined as the point of zero energy and not minimum energy, and i'm not sure which it is defined as, then at zero energy, electrons would have an extremely high chance of having fallen into the nucleus with an almost infinetessimal (but still possible) chance of being elsewhere, from +ve infinity to -ve infinity!

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: Ylide on 07/12/2003 12:24:56
gpan:  If I may make a correction, at 0 K, all atomic motion ceases.  The atoms are not moving (i.e. no translational, rotational, vibrational energy) and the electrons are in their lowest possible energy states...that doesn't mean the electrons themselves are not moving.

Temperatures of one one-billionth of a Kelvin have been reached...if the motion of the electrons in their orbitals were slowed by temperature, we would have violated Heisenberg already, as the electrons would be practically immobile at that temperature.

Anyway, don't nuclear repulsive forces keep the electrons from falling into the nucleus?

This message brought to you by The Council of People Who Are Sick of Seeing More People
Title: Re: Which way faster, east or west ?
Post by: qpan on 07/12/2003 17:00:22
Nuclear repulsive forces only occur between baryons- such as protons and neutrons. Electrons are leptons and not under the effect of the strong force. At very low temperatures, electrons have a very small amount of enery and are therefore far more likely to be in the lowest orbital and extremely unlikely to be anywhere else, but under heisenberg's law, the electron does have a (very) small probability for being elsewhere.
What is was saying in my other post was that wouldn't electron motion incite vibrational/rotational motion in the nucleus or neibouring atoms?
I don't think electrons are slowed by temperature decrease, as that would imply electrons just orbited atoms instead of just having areas of high probability (orbitals) which they are likely to be. The less energy an atom has, the more the high probability regions of finding electons moves towards the nucleus, so either the limiting case is the high probability region moves into the nucleus or to somewhere close above the nucleus, depending on what definition of absolute zero you use.

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
Title: Re: Which way faster, east or west ?
Post by: GlacierBlue on 10/12/2003 07:04:44
I hope I'm getting this right, because its 11:47pm and I'm tired. Your saying that you don't think that electrons can fall out of orbit when the temperature reaches one billionth of a degree above K because every atomic structure must have something in one of its orbits? This would explain why there is still some temperature I guess? The thing Im a little foggy about though is the fact that they say that they have reached a temperature close to -1.0e8 K. How do you measure something that cold? Temperature is a measurement of how much k.e. something has and if you can measure something, that imparts energy right? Isn't there something in Heisenberg's Uncertanty Principle about the process of observing something changes it?

If the multi-verse is a real construct then in some universe Im your God.
Title: Re: Which way faster, east or west ?
Post by: nandakumar on 28/12/2003 07:36:44
hi

both the planes will reach their destination at the same time. if the wind speed is equal, or nil, efficiency of the aircraft is equal.

This is because of the rotation of the atmosphere with the earth. it has no effect on the aircraft or the vehicle on the ground. They travael at the same speed unless and until you have local problems.

What you are thinking is that if you place the aircraft above, you will your destination in the western side. I too have thought  about this but it sounds different.

i think now your doubt is cleared.

hi iam a student of geology and currently doing my post graduate degree in remotesensing
Title: Re: Which way faster, east or west ?
Post by: GlacierBlue on 02/01/2004 23:20:34
Your post didnt clear up much. I had a hard time understanding you. Is english you first language? I thought that it was odd that you are doing your graduate work on remote sensing. What type of college offers a degree program in ESP? If my memory is correct, remote sensing is like out of body stuff, correct?

If the multi-verse is a real construct then in some universe Im your God.
Title: Re: Which way faster, east or west ?
Post by: Stephbaker on 29/01/2019 13:43:27
If you threw a ball from a moving car, it would travel with the car for a bit before gravity pulled it down....momentum.
If you pulled the chair out from under someone as they were sitting down, they would miss the chair and bust their a\$\$....deviance.

Now, my belief is that traveling westward would be faster. There's not enough momentum from the rotation of the earth to make a difference either way. However, the earth would move enough that a certain point (chair) would be moved from under the plane (a\$\$). So, I would speculate that west would be faster. (Not counting time changes)
But, my mind is now debating with itself. Great. I know it doesn't take much, but now I'm confused. Thanks alot!

Welcome to the forum, Mawea.

Wow, this is the best answer! Thanks, man
Title: Re: Which way faster, east or west ?
Post by: Janus on 30/01/2019 16:04:16
If you threw a ball from a moving car, it would travel with the car for a bit before gravity pulled it down....momentum.
If you pulled the chair out from under someone as they were sitting down, they would miss the chair and bust their a\$\$....deviance.

Now, my belief is that traveling westward would be faster. There's not enough momentum from the rotation of the earth to make a difference either way. However, the earth would move enough that a certain point (chair) would be moved from under the plane (a\$\$). So, I would speculate that west would be faster. (Not counting time changes)
But, my mind is now debating with itself. Great. I know it doesn't take much, but now I'm confused. Thanks alot!

Welcome to the forum, Mawea.

Wow, this is the best answer! Thanks, man
Except for the fact that it is wrong.
Title: Re: Which way faster, east or west ?
Post by: Petrochemicals on 31/01/2019 00:40:05
So is the proposed plan for future air travel involving hopping up into near-space, sitting there a little while as the earth turns beneath you, and then landing in the right place, at all feasible ?

Chris

"I never forget a face, but in your case I'll make an exception"
- Groucho Marx
Just like concorde, robot butlers, moon bases etc. Such a shame these things dont come to fruition.
Title: Re: Which way faster, east or west ?
Post by: Janus on 31/01/2019 16:36:02
So is the proposed plan for future air travel involving hopping up into near-space, sitting there a little while as the earth turns beneath you, and then landing in the right place, at all feasible ?

Chris

"I never forget a face, but in your case I'll make an exception"
- Groucho Marx
Just like concorde, robot butlers, moon bases etc. Such a shame these things dont come to fruition.
It would be a extremely inefficient means of travel.  When you launch your rocket upwards, it would still be carrying momentum from the Earth's rotation.  Any drift relative to the ground would be the result of Coriolis effect. If you went up 300 km, this difference works out to be ~ 20 m/sec relative to the ground, which is  72 kph or 45 mph as a rough estimate.* To reach that 300 km altitude, you would have to launch your rocket at over 2.5 km/sec, and if you it to stay there for any length of time, you would be burning fuel to "hover".    Pretty damn wasteful, if you ask me.

* to work out exactly what the effective ground velocity would be over the course of any "flight" would require delving into orbital mechanics.