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Physics, Astronomy & Cosmology / Re: Why do we have two high tides a day?

« on: 13/12/2018 07:33:24 »

D.C. and Colin2B:
Thanks for your words, and Merry Christmas and Happy New Year !
D.C.: beyond any "political correctness", I beg your pardom for my frequent rather "strong" words ...
Colin2B: I consider this thread should be kept open, just in case somebody else wanted to send some comments, or to ask any further question relative to the issue ... And thank you again !

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That CAN'T be true! / Re: Tides is the result of the rotation of the Earth and whirlpools

« on: 05/06/2018 07:52:39 »

link=topic=73127.msg543936#msg543936 date=1528121613]
The summary is that difference of gravitational force between nearest and furthest point on earth in earth-moon axis is too small to be the main cause of tidal bulge. Instead it is caused by the accumulation of forces on points outside of earth-moon axis.[/quote]
Thank you for your summary, but you have been too benevolent when watching and listening to that video.
The author explains that "accumulation of forces" (?) happens through a kind of hydraulic mechanism, that "squeezes" the oceans and mainly due to that the bulges are formed ... Rubbish !!
I´m pretty sure squeezing, if any, is quite negligible:
1) The active agent of the supposed hydraulic device would act on a relatively very small surface: a very narrow "belt" 90º away from sublunar point, less than 5º worth (Moon - Earth distance is app. 60 times the radius of Earth, and all pulls are almost parallel). On the rest of sea surface radial component of Moon´s pull are outwards, suctioning rather than squeezing !!
2) On that small area, where there is an inward component of Moon pull, the difference between that pull and required centripetal force for revolving is close to null: almost no "spare" pull, and therefore no tidal force.
3) And inward component of that difference is app. that tiny value divided by 60 ...
Quite NEGLIGIBLE compared to other intervening factors !!

3

That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 18/05/2018 11:16:15 »

Quote from: Fermer05 on Yesterday at 08:27:39
In the phase of new moon and perihelion, the clock will go fast or slow.
We have known about the effect of tide on clocks for decades.

Again, you are saying not fully coherent things:
"We have known about the effect of tide on clocks for decades": correct ...
But that doesn´t necessarily mean that "In the phase of new moon and perihelion, the clock will go fast or slow", as I said on #103.

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That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 17/05/2018 11:43:37 »

In the phase of the new moon or full moon, the pendulum clock will go faster.

I do agree with what said by Colin2B on #102. It´s a not working theory ...
And, apart from that, what quoted is erroneous. No honest experiment could show it is correct.
If seen otherwise somewhere, we all should be able to read the analysis of the experiment, and challenge it ...

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That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 16/05/2018 11:46:21 »

I think we're not thinking out-there enough.
How do liquids separate from solids, and by what tension of viscosity do liquids act like solids, and under what temperature variations, for instance.....

The influence of those factors in the generation of global tides is negligible.
By the way, when do you think liquid water could act as solid, due to high tension of viscosity?.
I hope you are not thinking huge amounts of water could act as water drops due to viscosity ...

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That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 16/05/2018 11:28:11 »

as the planet spins faster than the Moon rotates around it, and both these bodies are "in harmony", maybe the problem of explaining this is how gravity works according to contemporary theory?

I insist: mixing two different phenomena makes errors more likely ...
The Moon and our planet are certainly "in harmony" as you say, but logically with two cyclical movements of identical period of app. 28 days, rotating (the Moon) and revolving (the Earth) around their common center of mass (barycenter).
The daily spinning of our planet has nothing to do with that harmony ... Even we could say that it causes some changes kind of against that harmony, being the root cause of that the friction between water and solid Earth, and internally between different "drops" of water ... But that affects Moon-Earth dynamics significantly only in a very, very long term.   

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That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 15/05/2018 19:00:49 »

You say “a very long work of NOAA I can´t find now”. Can you describe what it covers as I might have a copy in my lecture notes.

Thank you. It was when I posted #13 that I could not find it, but I did localize it:
https://tidesandcurrents.noaa.gov/publications/Tidal_Analysis_and_Predictions.pdf
Most of the work deals about the huge variety of local costal tides, but it also has an interesting part analyzing root Moon and Sun related causes of tides.
I´ve already said on the other thread that, though they explain the issue in a similar way as me, they even go beyond what I say, because they use the term centrifugal force even for the whole Earth revolving ... But on Earth C.G., when considering it as a whole, only centripetal force is exerted (total Moon´s pull), and it is producing the revolving of whole Earth, a kind of free fall ... Any centrifugal force considered acting there would be fictitious, as far as I can understand.
It´s on other points of our planet, where Moon´s pull doesn´t match with centripetal force required for actual revolving, where internal stresses appear, both "moon-ward" and outward, and those last ones are real centrifugal forces.   

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That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 15/05/2018 11:34:14 »

The Natural ''flow'' of the ocean is East to West 

Apologies for posting in other peoples thread.

Come on! I always thought all threads are "own" by all of us ... as long as we have something reasonable to say (or at least we honestly think it is reasonable).
 What do you mean with "natural" flow? Just to try and analyze its cause, and consider the rest of what you have "left" me/us with ...

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That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 15/05/2018 08:30:14 »

It SURPRISES me this thread carries on. Two different phenomena are being discussed, and frequently mixed up due to that … kind of playing both football (soccer) and rugby on same field … a disaster !
I already mentioned that fact on #13 (more than 60 more posts since then, only two and a half weeks !!!)
“… as I have repeated this very morning on that linked site, that my arguments have always been about root "main" and general ocean tides. What, mainly due to Earth/Moon dynamics (but also to Sun/Moon dynamics) would really happen without local effects, small or rather big. Resonance in water "oscillation" may produce big effects.
And those tides would happen even if Earth did not spin daily, main cause of "whirlpools", as far as I can understand. I have not delved into the existing lot of local cases, but I´ve seen they are very complex, especially on a very long work of NOAA I can´t find now”.
And subsequently, erroneous things are being said, since the proposition of the question.
Long ago when I was a boy, I already realized that, e.g., strongest high tides were always at same time, and when full or new Moon, in Atlantic coast of Spain where I was in summer holiday.
And nowadays, just seeing the Moon in Madrid sky at a certain moment, I can tell how high is the tide at mentioned coast, and also if the tide coefficient is high or low, without any complicated maths or any additional information.
How “on Earth” the OP can say:
"The gravity of the moon does not reach the Earth”? … (!!!)
Has he never had any experience similar to mine?
I suggest anybody interested to have a look at :

where it´s clearly seen that daily movement of the bulges is only apparent, that they are almost still and it is the solid part of our planet (though also the bulk of ocean waters due to friction) what is actually spinning …
The formation of the bulges is a rather slow process (some 28 days the complete cycle, as far as Moon related tides are concerned, and one full year in the case of Sun related tides) … Nothing to do with all those daily local whirlpools, due to the much faster Earth spin, and with any other local singularity.
NO single local daily phenomenon should be used to try to refute the FACT that Moon and Sun gravitational pulls, together with inertial effects (unveiled by Newton long ago), are the root causes of “globalized” tides. Physical details on how those tides happen can be discussed, because even there is no general agreement on things such as centrifugal forces, and other issues inherent in the complexity of nature ... But mentioned FACT can be seen by everybody, and matches with BASIC physics laws !!! 

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That CAN'T be true! / Re: Rotating earth theory of two high tides a day

« on: 27/04/2018 14:58:20 »

Also this series of posts https://www.thenakedscientists.com/forum/index.php?topic=49715.0 by @rmolnav should be read in its entirety, it is essential to understanding the fundamentals of tidal effects.

Thank you.
I wish to add, as I have repeated this very morning on that linked site, that my arguments have always been about root "main" and general ocean tides. What, mainly due to Earth/Moon dynamics (but also to Sun/Moon dynamics) would really happen without local effects, small or rather big. Resonance in water "oscillation" may produce big effects.
And those tides would happen even if Earth did not spin daily, main cause of "whirlpools", as far as I can understand. I have not delved into the existing lot of local cases, but I´ve seen they are very complex, especially on a very long work of NOAA I can´t find now.

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Geology, Palaeontology & Archaeology / Re: Is Mt Everest the tallest mountain on Earth?

« on: 07/11/2017 21:19:49 »

It depends on where you count its height from ...
E.g.: Mt Everest is NOT the farthest point from Earth´s center.

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General Science / Re: Is a mass bouncing on a spring affected by gravity like a pendulum?

« on: 14/09/2017 19:02:16 »

#10
I agree with you.
Regarding terms mentioned in "to ignore friction along with countless other terms", we could bring up site latitude, Moon´s position at the moment, GMT, altitude, near or far from from big masses (mountains, amounts of ice there ...), actual composition of Earth´s crust in the area ...
Nature is far more complex than our simplifications !!!

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General Science / Re: What is centrifugal force?

« on: 13/10/2016 19:35:03 »

#50 Nilak
You say:
"So the centrifugal force is the effect of inertia when changing direction".
Not bad idea. But, have you realized that, after all, it is a way of expressing (in a particular case) the three Newton´s Principles?
Whatever happens with linear speed of an object, any change of its direction is a velocity vector change, an acceleration. That results in a curve trajectory.
That acceleration requires an acting force (2nd principle), towards the concave side of the curve (by the way, not necessarily a circumference): centripetal acceleration. If that is exerted (whatever the way) by object  A on B, B by INERTIA tries to maintain its own speed (1st principle), and exerts an equal but opposite force on A: (3rd principle).
But, apparently, you mean centrifugal force is "the effect of inertia" on the object that changes direction ... That seems to establish the idea that centrifugal force in a kind of fictitious force, just an "effect" of inertia.
Please kindly read my #50. There you can see I talk about the "infinite" pairs of centripetal/centrifugal forces acting on the particles of any rotating  object (or just with a curve trajectory). That can be considered an "effect" of inertia,  but it is a REAL force, and it doesn´t mean centrifugal force is not  fundamental.