Variation in tides

In message . com,
Weatherlawyer writes

Jonathan Silverlight wrote:

they are caused by two bodies dragging water around a body with various
irregularly shaped land masses.
One of the most entertaining accounts of this I know of is Fritz
Lieber's novel "The Wanderer", where the situation is complicated by the
appearance of an Earth-mass body near the Moon prompting one character
to exclaim "At last, a really challenging example of the three-body
problem"

When you use emoticons it means the joke needs explaining. When the
joke needs...
Ah never mind. Never mind the drivel,

You're one post away from my kill file, and I'm being generous. You're
just another troll with a fake hotmail address posting via Google. Or a
complete idiot. Or both.

I want to know how the moon can drag a particle up from the earth
considering the masses and distances involved.

Gravity. Works over infinite distance, though it obeys an inverse square
law (tides obey an inverse cube law).

And why if it works on
volumes with very little gravity of their own, it doesn't have the same
effect on more imposing particulate.

Could you translate that into standard English?


Besides which, if the three body problem is in a constant state of flux
as one planet invokes movement on another, how does the distant planet
affect subdivisions of the other.

And another thing: If the moon can raise water on the earth, why can't
the earth raise sand on the moon? IIRC a crystal of silicon dioxide or
whatever sand is, is some 3 times more dense than water but the moon's
gravity is 1/6th.
I would have thought that on the theory most here are defending
(without the benefit of a schoolboy's primer may I add) the moon would
have tidal mountains and hills.


That's an odd way of putting it, but it does. If you took the trouble to
learn anything at all about the subject, you would find that the Moon's
shape is permanently deformed from a spherical shape. Look at
http://www.astronomycafe.net/qadir/q277.html for instance. Because the
Earth has 81 times the mass of the Moon it has not yet stopped rotating
relative to the Moon, so the bulge moves round the planet.

Steve Taylor wrote:
Weatherlawyer wrote:

And another thing: If the moon can raise water on the earth, why can't
the earth raise sand on the moon?

It does, or else how is the moon's rotation locked to the earth ?

So the entire product of earths gravity is given the attention of the
satellite.

A point I agree with. As is the obverse. The entire attraction of the
earth for the moon is occupied in centralising it in the position it
maintains in the two body problem. So how come there is enough left
over for playng around with its puddles?

Physics in the reply might not come amiss.

Jonathan Silverlight wrote:

I would have thought that on the theory most here are defending
(without the benefit of a schoolboy's primer may I add) the moon would
have tidal mountains and hills.

That's an odd way of putting it, but it does. If you took the trouble to
learn anything at all about the subject, you would find that the Moon's
shape is permanently deformed from a spherical shape. Look at
http://www.astronomycafe.net/qadir/q277.html for instance. Because the
Earth has 81 times the mass of the Moon it has not yet stopped rotating
relative to the Moon, so the bulge moves round the planet.

And pray tell why they are not quadurnal. They are not even diurnal. If
the moon can raise the tides twice a day, surely the earth can do one
better?

Do you understand the laws of physics by any chance? What does the word
physics mean to you?

Weatherlawyer wrote:
Jonathan Silverlight wrote:

I would have thought that on the theory most here are defending
(without the benefit of a schoolboy's primer may I add) the moon would
have tidal mountains and hills.

That's an odd way of putting it, but it does. If you took the trouble to
learn anything at all about the subject, you would find that the Moon's
shape is permanently deformed from a spherical shape. Look at
http://www.astronomycafe.net/qadir/q277.html for instance. Because the
Earth has 81 times the mass of the Moon it has not yet stopped rotating
relative to the Moon, so the bulge moves round the planet.

And pray tell why they are not quadurnal. They are not even diurnal. If
the moon can raise the tides twice a day, surely the earth can do one
better?

Why should it be? Do you have any idea how long a lunar "day" actually
is???

The moon has already become gravitationally locked in synchronous
rotation with its orbital period because of tidal drag. Hint: that is
why it always shows roughly the same side to the Earth (ignoring for
the perturbations and its elliptical orbit) Or hadn't you noticed?

If you want to better understand physics in a rotating frame of
reference try moving your arm in one of those centrifugal spinning
fairground rides. And be careful that you do not knock out your
neighbour...

Do you understand the laws of physics by any chance? What does the word
physics mean to you?

Several of us not only understand the laws of physics but can derive
the equations that govern the raising of tides on a planet by a
satellite. It isn't all that difficult to compute from first principles
for a uniform sea on a spherical planet...

http://csep10.phys.utk.edu/astr161/lect/time/tides.html

Is a reasonable description of the basic mechanism.

NB Real detailed tidal calculations have to include friction,
irregular coastlines, continents and varying depths of ocean. For some
strange reason this subject attracts net kooks.

Regards,
Martin Brown

Weatherlawyer wrote:
The entire attraction of the
earth for the moon is occupied in centralising it in the position it
maintains in the two body problem. So how come there is enough left
over for playng around with its puddles?

Physics in the reply might not come amiss.

What mechanism do you propose, other than mass, and distance for this
"apportioning of the gravity" ?

Steve

Martin Brown wrote:
Weatherlawyer wrote:
Jonathan Silverlight wrote:

I would have thought that on the theory most here are defending
(without the benefit of a schoolboy's primer may I add) the moon would
have tidal mountains and hills.

That's an odd way of putting it, but it does. If you took the trouble to
learn anything at all about the subject, you would find that the Moon's
shape is permanently deformed from a spherical shape. Look at
http://www.astronomycafe.net/qadir/q277.html for instance. Because the
Earth has 81 times the mass of the Moon it has not yet stopped rotating
relative to the Moon, so the bulge moves round the planet.

And pray tell why they are not quadurnal. They are not even diurnal. If
the moon can raise the tides twice a day, surely the earth can do one
better?

Why should it be? Do you have any idea how long a lunar "day" actually
is???

The moon has already become gravitationally locked in synchronous
rotation with its orbital period because of tidal drag. Hint: that is
why it always shows roughly the same side to the Earth (ignoring for
the perturbations and its elliptical orbit) Or hadn't you noticed?

Librations of the moon aside, the fact that the mountains on the moon
are not crawling toward the equator tends to disprove the facts as you
describe them does it not?

Do you understand the laws of physics by any chance? What does the word
physics mean to you?

Several of us not only understand the laws of physics but can derive
the equations that govern the raising of tides on a planet by a
satellite. It isn't all that difficult to compute from first principles
for a uniform sea on a spherical planet...

http://csep10.phys.utk.edu/astr161/lect/time/tides.html

Is a reasonable description of the basic mechanism.

NB Real detailed tidal calculations have to include friction,

Ah the get out clause. Quite so. And the fact remains that even with
all the superduper computers available this problem defies resolution:

irregular coastlines, continents and varying depths of ocean.

For some strange reason this subject attracts net kooks.

Perhaps it is the weather?

The amount of spare energy or whatever left over from the two body
problem leaves little power for the moon to directly raise tides.
Otherwise the Gulf Of Mexico and a few other regions would have massive
tides friction or not. And they would continue to have them one tidal
day at a time.

Even allowing for the fact that water is a prety near perfect fluid, it
has to answer to physics when it reaches inlets such as tha Bay of
Fundy and Avonmouth.

Once it overcomes a restriction and allowing for the fact that the moon
has often passed the zenith for the region involved:

Simple schoolboy physics demands that there is only one high tide and
one low tide per tidal day. And for restricted bays the power should be
muted not enhanced.

Is that good enough for you? Or would you rather I let you sleep,
dozey?

In message .com,
Weatherlawyer writes

Martin Brown wrote:
For some strange reason this subject attracts net kooks.

Perhaps it is the weather?


Gobbledegook snipped. That's you he's talking about :-)


Is that good enough for you? Or would you rather I let you sleep,
dozey?


OK, you offensive little troll. I'm putting you out of my misery and I
suggest everyone here does the same.
Flush.

"Weatherlawyer" wrote in message
ups.com...
Et tu tute.

Needless to say Dozey II completely ignored the real problem. Making me
the scapegoat evidently works in his world.

Either the moon is part of the two body problem or it is free to play
with loose particulate floating on or near the surface on the earth.
And in some way -as yet to be properly defined, on the other side of
it.


Oddly perhaps, Galileo seems to have had the same problem in understanding
the issues. However, he felt that he had to make the case that a
heliocentric system supported the 'two tides' phenomenon whereas a true
geocentric system would tend to imply a 'one tide' outcome.

It has been argued that his inability to prove it to his own satisfaction
meant he tried to bluster and bully his position rather than being able to
put forward a strong intellectual argument that could stand on its own
merit.

This meant that despite the initial support of many in the church hierarchy,
he actually lost the argument because he could not marshall his arguments.

Is this relevant in this thread ? I think so.

OG wrote:
"Weatherlawyer" wrote in message
ups.com...
Et tu tute.

Needless to say Dozey II completely ignored the real problem. Making me
the scapegoat evidently works in his world.

Either the moon is part of the two body problem or it is free to play
with loose particulate floating on or near the surface on the earth.
And in some way -as yet to be properly defined, on the other side of it.


Oddly perhaps, Galileo seems to have had the same problem in understanding
the issues. However, he felt that he had to make the case that a
heliocentric system supported the 'two tides' phenomenon whereas a true
geocentric system would tend to imply a 'one tide' outcome.

It has been argued that his inability to prove it to his own satisfaction
meant he tried to bluster and bully his position rather than being able to
put forward a strong intellectual argument that could stand on its own
merit.

This meant that despite the initial support of many in the church hierarchy,
he actually lost the argument because he could not marshall his arguments.

Is this relevant in this thread ? I think so.

I don't see Gallileo as a dozey plonker. He did (so I have heard) argue
with Keppler on the subject. I just assumed that Galileo was more
familiar with Mediteranean tides than Keppler and less familiar with
Atlantic ones.

It is a problem that even Newton sidestepped, referring to the
Aethiopian Sea as the one where the lunar theory held true. Obviating
the obvious though.

Dr John Stockton wrote:

What's the biggest-scoring legal move in Scrabble?

I suspect that the answer is not known for certain. Here are some
excerpts from Gyles Brandreth, _The Complete Book of Scrabble_, Robert
Hale, London, 1980:

"The highest known score achieved at a single move in a real game is 374
points. This was achieved by playing the word QUETZALS across two
triple-word-score squares, and getting Z on a double-letter-score
square. This score was made by Darryl Francis, of Wandsworth, London,
on 12th September 1973.

....

In a idealized game, the highest score yet discovered for _one single
move_ is 1961. This idealised move was devised by Ron Jerome, of
Bracknell, Berkshire, in May 1974. The move involved playing all seven
tiles, combing them with eight already on the board, to form a 15-letter
word, which stretched across three triple-word-score squares. As well
as making this 15-letter word, the move also created seven words
perpendicular to it, three of them stretching across triple-word-score
squares.

The 15-letter word that was played was BENZOXYCAMPHORS. The seven other
words were DAFFODILLY, GULLISH, JINNYRICKSHAWS, PROVERB, SQUANDERMANIAC,
VAGABONDAGER and WERTUZ. (The words DAFFODILL, GULLIS, JINNYRICKSHAW,
PROVER, SQUANDERMANIA, VAGABONDAGE, and WERTU were already on the
board.)

BENZOXYCAMPHORS - Webster's New International Dictionary, Second edition
DAFFODILL - Oxford English Dictionary
DAFFODILLY - Chambers
GULLIS - Oxford English Dictionary
GULLISH - Chambers
JINNYRICKSHAW(S) - Oxford English Dictionary
PROVER - Chambers
PROVERB - Chambers
SQUANDERMANIA - Chambers
SQUANDERMANIAC - Webster's New International Dictionary, Second Edition
VAGABONDAGE - Chambers
VAGABONDAGER - Oxford English Dictionary
WERTU - Oxford English Dictionary
WERTUZ - Oxford English Dictionary"

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