Coriolis Effect--Science or Superstition?

[Erasmus00]

Until I see data like that, I will remain firmly on Sir Isaac's side. I believe Earth is an inertial frame of reference. That the effect of Earth's rotation here in Earth is exactly proportional to the degree to which said rotation changes Earth's form from a sphere. That a sphere is how nature describes an inertial field of reference.

 

You seem to have a bit of a flaw in your understanding of Newton. The coriolis effect is a straight forward application of Newtonian physics that Newton himself certainly would have agreed with. If the Earth is rotating, which is obviously is, Newtonian mechanics predicts the Coriolis effect.

 

And that an ascending rocket rotates precisely in synch (angular rotational velocity) with Earth right up to the precise moment that orbital V is reached (that straying from a natural tendency to rotate precisely in synch with Earth is a byproduct of escaping Earth's gravitational field through sufficient horizontal V).

 

You act is if gravity somehow keeps things rotating. I.e., everything inside Earth's gravity is kept rotating by the gravitational field. The problem is, though the Earth is rotating, its gravitational field is more or less spherically symmetrical. I.e. the field knows nothing about the rotation.

 

Also, those things orbitting Earth have NOT escaped the gravitational field at all. It is the gravitational field that keeps them orbitting.

-Will

[cnewtongifford]

The coriolis effect is a straight forward application of Newtonian physics

 

the field knows nothing about the rotation.

 

Also, those things orbitting Earth have NOT escaped the gravitational field at all.

-Will

Erasmus: Thank you for those interesting points. Obviously you are a skilled mathematician. Let's suppose that a Hollywood producer heard about you and retained you to help him put together a budget for an upcoming movie. It was to be a 'road trip' movie, with a lot of the action involving the two big stars riding around in a blue convertible--actually the plan was to have the convertible parked on a sound stage in front of a scenery backdrop--where projected scenes gave the illusion that the convertible was moving. The 2stars had different contracts. One was to receive $5.00 per travel mile during filming, the other $8.50. What data would you need to calculate the total projected travel pay for both stars?

Would there be any relationship between the projected amount of energy used by the convertible during these flying-scenery scenes and the $ amount for travel pay for the 2 stars?

Coriolis would have said, "Yes", and busily gone about the business of creating a formula to calculate the travel pay. And just to show off for his friends, he would have probably worked up a formula for calculating the variance between the travel pay for the 2 stars for any given particular scene.

Newton, on the other hand, would point out that the blue convertible possesses no momentum, that it does not physically go anywhere,

that therefore the amount of projected travel pay is exactly the same as the amount of energy projected to move the convertible through those scenes (Zero). So the difference between the travel pay of star A and star B will be Zero. ( If in fact the sum of zero and zero is zero).

That is not a perfect analogy, but is the best I can come up with on short notice. Newton would agree that if the physical rotation-derived momentum of an object sitting at the equator is zero, and you transport that object far to the north and set it down again, wherever it lights its physical rotation-derived momentum will still be zero. So mathematically, the change in that object's rotation-derived momentum will be zero (zero +/- zero).

One of the many ways Coriolis cheated was to cherry-pick the portions of the dynamics of rotary motion which suited his scheme. No centrifugal force. No centripetal force. No forces or force byproducts of any kind while an object was 'stationary'. Was it by chance that the 'effect' he hypothesized was--with the technology of his day--untestable?

I guesstimated, going in, that out of 1,000 smart people who might apply their minds to this subject, only 1 would succeed in spotting Coriolis for the fraud that he was.

Isn't Coriolis directly in conflict with the Newtonian conclusion that Earth, despite her travel through space, is an inertial environment?

I totally agree that 'the field knows nothing of the rotation'. Which strikes me as directly contradictory of the underlying assumption of Coriolis. The rotation (as well as the solar orbit) is an inherent, inseparable part of the gravitational field. That orbit and rotation do not involve the application of energy. If not, what is the energy source--and usage--involved in those field-motions?

Orbiting objects most certainly HAVE escaped the field--to a large extent. All the way up to orbit V, every meter of travel represents the application of energy. At the moment of reaching orbit V there is a wonderful transformation. Linear velocity continues--indefinitely--without any continued application of energy. I think that's what orbit amounts to--which is a very, very significant departure from Earth-bound rules of motion. "Momentum" inside a gravitational field and "momentum" outside that field are entirely different animals. In a state of orbit, an object's connection to Earth is tenuous--Earth acts as a big tether only.

The key to seeing Coriolis for what it is is right there in the simple mechanics of orbiting objects. It is also right there in a glass of water sitting on a table. It is also right there in the stability of the spherical form of all of these orbiting rotating gravitational fields. Does the sphere represent a completed physical process--or is it a work in progress?

Thanks again for your remarks. CNG

[Pyrotex]

Who decided to include that data in rocket launch balistics? When? On what scientific basis?

Is there any actual data comparing the balistics of East vs West launches, factoring out meteorological variables?

Until I see data like that, I will remain firmly on Sir Isaac's side. I believe Earth is an inertial frame of reference. That a glass of water left alone will be still. That an arrow shot straight up (from any latitude) will fall straight down. ...

Cnewt,

the questions you ask reveal more about you than about your original query.

 

"Who decides...?" Do you really think that this is left up to some "ivory tower authority" as if it were a theological question?

 

"On what scientific basis?" "...any actual data?" Come on now, we have been firing (big) rockets off the Earth ever since the V-2 in early 1940's. We have more than HALF A CENTURY of ballistic experience verifying that the equations of flight will indeed match the actual flights and vice-versa.

 

Putting satellites in orbit is done with high precision; errors of apogee, perigee are often measured in tenths of a kilometer or smaller. That's the size of a football field. Radar can determine its position much finer than that. Velocity can be measure by Doppler effect to within a fraction of a meter per second.

 

Change of subject. Isaac Newton did not make the claim you suggest: that the surface of the Earth constituted a non-rotating Frame of Reference (FOR). The suggestion that "inertia" means "in the Earth" and your conclusion that Newton INTENDED this to MEAN "a non-rotating Frame of Reference" simply does not follow. That is not rigorous scientific logic. What that IS is "pulpit logic".

 

Yes, your questions say a lot about you and your train of thought. Does the word "troll" mean anything to you? Just asking. No offense intended.

[Erasmus00]

Newton would agree that if the physical rotation-derived momentum of an object sitting at the equator is zero

 

Newton wouldn't agree with that at all. Objects rotating with the Earth DO have momentum. If you could suddenly turn of gravity, everything flies out at straight lines.

 

One of the many ways Coriolis cheated was to cherry-pick the portions of the dynamics of rotary motion which suited his scheme. No centrifugal force. No centripetal force. No forces or force byproducts of any kind while an object was 'stationary'.

 

You seem to have a flawed understanding of Coriolis. He didn't throw out any of Newton.

 

Isn't Coriolis directly in conflict with the Newtonian conclusion that Earth, despite her travel through space, is an inertial environment?

 

If the Earth traveled in a straight line, it would be inertial. However, it is undergoing two different rotational motions. It spins on its access and orbits the sun. Rotational motion is NOT inertial. Newton wouldn't have thought it was.

 

The rotation (as well as the solar orbit) is an inherent, inseparable part of the gravitational field.

 

Ignoring GR, the rotation doesn't have any effect at all on the gravitational field. They are totally seperate. A non-rotating spherical body has the same field as rotating one.

 

Orbiting objects most certainly HAVE escaped the field--to a large extent.

 

Not at all. Calculate the magnitude of the Earth's gravitational field for an orbit. Its quite large. All thats happening in orbit is that as the object falls, it "misses" the center of the Earth because its linear momentum carries it outward.

 

Linear velocity continues--indefinitely--without any continued application of energy.

 

Its linear velocity does change. It continuously changes, otherwise it would go in a straight line, not a circle. Remember, velocity is magnitude AND direction.

 

Your queries into the coriolis effect could benefit greatly from an introductory mechanics book. I'd highly recomend volume one of Feynman's lectures.

-Will

[CraigD]

That's where the word inertia comes from: IN EARTH.

This is an interesting claim, but not one supported by any historic or etymological evidence of which I’m aware.

 

The word “inertia” is generally believed to have appeared around 1618 in Kepler’s “Epitome Astronomiae Copernicanae”. He appears to have invented the word to describe the quality of being inert. The word Latin word “inert” is ancient, and in the common usage meant “idle” or “lazy”. It appears to derive from the phrase “in ars” in the Indo-European ancestor language of Greek and Latin, meaning, literally, “without skill” or “without art”.

 

Had an academic Latin user like Newton wished to write a word meaning “in Earth”, he would have used “interred”, a word still in the common English usage meaning “burried”. Someone unfamiliar with Latin might contract “in Earth” into “inert”, but Kepler and Newton were very familiar with Latin, as were, almost without exception, all natural philosophers of their period.

[cnewtongifford]

Objects rotating with the Earth DO have momentum.

 

I'd highly recomend volume one of Feynman's lectures.

-Will

 

Thank you Will:

 

Been away from this site for a few days. Have made renewed attempts to extract some Coriolis-relevant data from NASA. Can't get any replies--much less answers.

 

Perhaps you or someone else knows the right buttons to push.

 

When Nasa plots a shuttle launch trajectory do they factor in anything Coriolis-related? The ELV & Shuttle Launch Trajectory Support dept of NASA's Flight Dynamics Facility no doubt could answer that--if you could get their attention. If Not, why? If Yes, on what basis?

Have any comparative satellite launch azimuths ever been employed from the same pad--e.g: one East, another West, to compare the performance? One North, one South to compare the variation from original launch-to-orbit geodesic? I know what Feynman says we could expect. He and everybody else tell us that such tests would PROVE Coriolis (because OF COURSE Earth's rotation represents momentum).

 

'Of Course It Does' isn't very scientific.

 

CNG

 

 

CNG

[Qfwfq]

CNG,

 

sit on a merry-go-round horse when it is stationary and throw a baseball at the central post. If you're anywhere near average schoolyard ability you'll be able to aim at the target easily.

 

Do the same while the ride is going steadily around and see what a difference it makes. I'm sure you'll notice.

[Pyrotex]

...Have made renewed attempts to extract some Coriolis-relevant data from NASA. Can't get any replies--much less answers....Have any comparative satellite launch azimuths ever been employed from the same pad--e.g: one East, another West, to compare the performance? ...

You already have received relevant data from NASA. Me. I worked in the Lab in Building 16 that calculates orbits. And the answer to the question above is 'yes'. Shuttles have been launched from the same pad in Florida to the SE and to the NE, and to several directions in between. The trajectories match the predicted paths, including all Coriolis and atmospheric forces, to within a few tens of feet. That is far more accuracy than required to demonstrate that the Coriolis force is real.

 

At the pad in Florida, the Earth's rotation is, say, 800 mph East. A launch to orbit confirmation takes, say, 15 minutes or 1/4 of an hour. If the Coriolis force was a hoax, then in 1/4 hour, there would be an error of 800/4 or about 200 miles! We don't see that. We see errors of a few tens of feet.

 

Now it is your turn to say, "But that is NOT real science! That isn't real evidence! I don't accept that! Waaaahhhhhh!!!!" :surprise:

[TheBigDog]

Pyrotex,

 

My uncle worked at Vandenburg AFB for 20 years. He explained to me that they launched rockets into polar orbit from there because of the latitude. Is that in responce to dealing with corialis effect too?

 

Bill

[Pyrotex]

Pyrotex,

 

My uncle worked at Vandenburg AFB for 20 years. He explained to me that they launched rockets into polar orbit from there because of the latitude. Is that in responce to dealing with corialis effect too?

Hmmmm... I know that Vandenburg was intended to launch into polar orbits and other "military" orbits that even went a bit West of the pole. Ferret orbits, they were called. I thought the reason was, from Florida, you would have to launch over cities in Georgia, Tennessee, etc, to achieve those orbits. From VAFB, the launches could be over water.

[Qfwfq]

All this stuff about rockets and orbits is only confusing the matter.

 

Coriolis isn't really as essential as you think for the difference between eastward and westward orbits. If you worked it out you'd see that, actually, Coriolis goes against an eastward orbit. Only slightly though, for a low orbit. A body falling with no tangent force applied will undergo an eastward acceleration but a body shot vertically upward will deviate westward.

[Pyrotex]

...

(deleted)

[Qfwfq]

I have a degree in physics and doing the math is easy for me.

Same with me. I get the impression you have misunderstood my post.

[Pyrotex]

Same with me. I get the impression you have misunderstood my post.

YES!! :hihi: I confused you with someone else. :hihi:

And then I jumped to concussions. :lol:

Which is amazing cause I wouldn'tuv thought I could jump that far. :lol:

More later, after I have a cup of coffee.

[TheBigDog]

I didn't mean to cause any confusion. I don't have a physics degree, and would struggle to do the math even if I knew the formulas. I think I understand the mechanics of this whole thing from a visual perspective. I am just trying to learn a bit more by following this thread.

 

I remember seeing these giant pendulums at museums. They always line up the little pegs in the morning so as the earth rotates under the pendulum it knocks down the pegs around the circle. My dad explained that the inertia of the pendulum was so great that it was causing it to maintain a constant direction despite the rotation of the earth - or something to that effect. I was always fascinated by such displays. I think I understand the effect. I don't don't understand the contraversy.

 

Bill

[Pyrotex]

I didn't mean to cause any confusion. ...

Sorry, Bill, but it wasn't you that caused me to derail. Actually, I'm glad it wasn't you. I thought cnewtongifford had posted one of his [adjective deleted] anti-coriolis posts and I, well, I called in an F-15 airstrike on his punkin head.

THEN I realized my error. :hihi: :lol: :lol: :hihi: :hihi: :hihi: :lol: ;) :lol:

[Qfwfq]

It can happen to all of us Pyrotex. Cheers. :hihi:

 

I don't have a physics degree, and would struggle to do the math even if I knew the formulas. I think I understand the mechanics of this whole thing from a visual perspective. I am just trying to learn a bit more by following this thread.

Another classic test is to drop a lead weight off a very high tower on a widless day. Actually the tower would need to be very, very tall but the effect can be discerned if things are done properly. Try thinking about what will happen.

 

Controversy? Yeah, well, today we "know" that Earth is rotating and we take it for granted, otherwise things would be less obvious. Actually, the matter is quite subtle. What exactly does "inertial frame" mean?