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4
TR Memescape
i prefer to make fun of idiots online because its the most effective way to convince the lurkers who are on the fence and its really such a shame that the only options are making fun of idiots or engaging in pointless intellectual discussions with people who will never be convinced man i really wish there were a third way thatd be pretty cool dont you think so bart but really its all for the lurkers and calling people dummies on the internet makes a real difference and saves lives we are super important dont forget it buddy.
5
Science / Re: The Tides ... Take 5
And one more question. I am assuming when he talks about the moon on a tower there is no rotation involved.  But he doesn't specify that.  If there is a rotating earth with the moon on a tower, isn't that a different issue?

You mean, the moon is on a tower planted on the earth, which rotates (so the moon stays over a fixed location on the earth's surface)?  Or the moon is on a tower planted on something else, while the earth rotates nearby (so the moon's position above the earth's surface changes)?
I somehow missed your post before.

I mean if the moon is attached by a tower to the earth.

I think we covered this, but one more time.

Several different situations.  If the moon is on a tower, so it is exactly still in regards to the earth.  One bulge?

But if on a tower, and the earth is rotating?  24 hour a day rotation that is? One bulge or two?

If the moon is on a tower, no 24 hour spinning, but the two are rotating around their shared center of gravity monthly?  What then? (is that even possible?)


6
Science / Re: The Tides ... Take 5
Most of what I learned early on, about tidal forces, was from Beowulf Shaeffer.
7
Science / Re: The Tides ... Take 5
To me the solar orbit tide bulge is easy to visualize.  But it seems to involve inertia as well.  The part of the planet farther away orbits more slowly than the near side, causing tidal forces, which stretch the planet.  If the planet wasn't solid it would turn the planet into a ring. Right?

But the lunar orbit tidal force is harder to mentally grasp.  Even when it is obviously much stronger.
8
Science / Re: The Tides ... Take 5
OK, two explanations.

(1) The surface of the ocean should be an equipotential surface.  With the moon and earth fixed in place, you can easily compute the shape of that surface.  Relative to the case with no moon (where the equipotential surface would be spherical, at least assuming the earth itself is) the surface is deformed towards the moon everywhere.  So there is a bulge under the moon, and a depression opposite the moon.

(2) The moon's gravity is pulling the earth's ocean towards it.  The ocean is not solid so it can deform, while the earth's surface and the moon's are held fixed by the tower.  Obviously, the earth's ocean will be pulled towards the moon by the moon's gravity, so it will stretch towards the moon on the near side and get pushed towards it on the far side.

Clear?
That part is easy and clear.  It's the second bulge, see previous post.  (you slipped in)
9
Science / Re: The Tides ... Take 5
 
To cut to the chase, if the tidal effect is from motion (which it seems has to be the case), the the explanation for the second bulge using the gravity gradient as the reason does not make sense.  If it was just due to gravity there would be no second bulge.  Right?

No, not really right.  Remember, the (orbital) motion is itself due to gravity.

With just gravity (which implies orbital motion), there are two bulges because of the gradient in the gravitational force.  With gravity plus another force - the tension in the tower, for instance - you have to also take that other force into account, and it swamps the gradient and produces only one bulge.

Sometimes people talk about gravity producing the near side bulge and "inertia" producing the far side bulge.  That's not a good way to explain it, but I wouldn't say it's totally wrong either - after all, there is an equivalence between gravity and acceleration.
That is exactly what I want to know about. "Sometimes people talk about gravity producing the near side bulge and "inertia" producing the far side bulge" So is it inertia or not?  Is the slow monthly orbit around the earth/moon center of gravity causing the tides?  That's the only orbit that is involved in the lunar tide.  Right?
10
Science / Re: The Tides ... Take 5
The reason that doesn't create two bulges when the moon is on a tower is that it ignores the main component of the force, the part acting on the center of mass, which is directed towards the moon at all points on the earth's surface.  You can (and should) ignore that part when the two bodies are in free fall, but not when they are connected by a tower or held in place in some other way.
That's the part I want you to explain. 
11
Science / Re: The Tides ... Take 5
To cut to the chase, if the tidal effect is from motion (which it seems has to be the case), the the explanation for the second bulge using the gravity gradient as the reason does not make sense.  If it was just due to gravity there would be no second bulge.  Right?
12
Science / Re: The Tides ... Take 5
This also is what is being said about the sun.  If the earth was not orbiting the sun there would be just one bulge from the sun as well.

Correct?

If they were both held in place, yes.  It's just like the moon.
That is exactly what I thought.

Now, the following is a new issue (as far as I can recall) in this discussion.  And it's difficult to explain with just words.  The simplest start would be those vector lines for the gravity gradient.  When they are shown (to explain the bulges), it isn't just the gravity being shown,  It includes the rotation as well.  Correct?

I suppose there are also atmospheric tides, which again should be fairly simple.
Yes, but the daily solar heating of the atmosphere dwarfs the tidal effect, so they are there, but of little importance.
13
Science / Re: The Tides ... Take 5
 This of course applies to the solid earth tide as well.  The deformation of the solid earth (which we do know is twin bulges, so to speak), is from the orbiting motion.  Both the moon earth orbit, and the earth orbiting the sun.
14
Science / Re: The Tides ... Take 5
This also is what is being said about the sun.  If the earth was not orbiting the sun there would be just one bulge from the sun as well.

Correct? 
15
Science / Re: The Tides ... Take 5
However if the moon and earth were in a geosynchronous orbit, there would be two bulges, stationary with respect to the earth's surface, one under the moon and one on the opposite side.
So the motion creates the tides, not just the gravity gradient?  Not the earth spinning, but the orbit of the moon and earth? 

This sounds like what is being said here
 "produced by the combined effect of the gravity of the Earth and the Moon, and the centrifugal force originated from the rotation of the system of the Earth and the Moon in an inertial frame"? (source)

I'm just trying to establish the simplest things here.






16
Science / Re: The Tides ... Take 5
And one more question. I am assuming when he talks about the moon on a tower there is no rotation involved.  But he doesn't specify that.  If there is a rotating earth with the moon on a tower, isn't that a different issue?

You mean, the moon is on a tower planted on the earth, which rotates (so the moon stays over a fixed location on the earth's surface)?  Or the moon is on a tower planted on something else, while the earth rotates nearby (so the moon's position above the earth's surface changes)?
I'm not saying anything.  I am asking what you think he is saying.



The moon on a tower (so it is not orbiting) seems to be a different issue than non rotating, but in either case, what do you think?

If the moon is on a tower, so no orbit, what would happen?  He clearly says one bulge.

Same for non orbiting of the sun, one bulge.  It seems motion is needed for tides.




17
Science / Re: The Tides ... Take 5
The following is a different matter.
It's exactly why I asked you if the tide would be the same in the canal, if it was 21,000 m deep, instead of 4000 m deep.  And then I asked about a canal 10 meters deep.
And I answered that, years ago.  The tide will not be the same, because the depth determines the free wave speed, and the free wave speed determines the phase for a given driving frequency (and affects the amplitude).  However, for all depths the tidal wave speed will be the same, as always for a driven oscillation in steady state.
I understand exactly what you are claiming, that the depth only changes the timing of the tide bulges in a canal. That shallow means the bulges will be "out of phase", but they will still be moving at 1000 mph.

I mean you wrote " for all depths the tidal wave speed will be the same", so that much is clear.  What you avoid answering is how and why you think this would be the case. 

18
Science / Re: The Tides ... Take 5
And one more question. I am assuming when he talks about the moon on a tower there is no rotation involved.  But he doesn't specify that.  If there is a rotating earth with the moon on a tower, isn't that a different issue?

You might view this as trolling (which I find humorous), but after 10 years of discussing this, and with you being pretty much the only person still interested, in what Universe would anyone think I am trolling you?

I am not stating anything, I am asking you what you think about a scientific view, put forth by multiple authors. 

Just as I asked you, what you were trying to ask, in your post about this matter.
19
Science / Re: The Tides ... Take 5
If you avoid simply answering this simple question, there is no movement forward. 

You almost asked me the same question, but you made it impossible to know if in your question there was movement involved.  I asked you to clarify, and you avoided answering that as well.

In the pages I am asking about he leaves no room for doubt.



He is saying with no rotation there is one bulge,  If you asked me if I agree with that, I would have said yes.  Because I simply believe what an expert wrote about it.  But I want your view on it.

Is there any part of this that you don't understand?  By this I mean what I am asking you?

20
Science / Re: The Tides ... Take 5
I am asking you to get your hard nosed math view of this.

There are multiple pages by esteemed scholars that flat out say "the centripetal force of the rotation of the earth and moon" is not the right answer.  We have discussed this at lenght, as well as the gravity vectors and the two bulges.  Like, a lot.

I am asking you one simple question, but you avoid answering. 

Is the reasoning in the Gravity book right or not?  He plainly states if there is no movement, and the moon is suspended on a tower, there is one bulge, from the gravity of the moon.  Do you agree with this?

Page 81 and 82

21
Science / Re: The Tides ... Take 5
I've never avoided answering anything -
Jesus Christ not only do you not answer, you waste time typing out even more false statements.

So what causes the other bulge?

If you are actually asking, I'd be happy to explain it.
After 10 years, and with you being about the only person left responding, what the hell makes you think I am just yanking your chain?  Seriously.

Your response is avoiding answering, but you seem unable to understand this point.  It's why I said you can't grasp the simple things.

The book "Gravity" clearly states that if the moon was suspended somehow in a tower, and the earth didn't rotate, the ocean response would look like this.



I quoted and linked to it, as well as the following.

Quote
Under these idealized conditions, we find that the moon's gravity attracts the surface of the ocean toward the moon. This creates a tidal bulge on the side of the Earth that faces the moon, like in the image below.

On the opposite side of the earth, another tidal bulge also is created. This is because the centripetal force of the rotation of the earth and moon "throws" water to this side of the Earth to balance the center of mass.

The question is very simple.  We have two linked sources (and many others over the years) explaining that gravity alone, no rotation, would simply cause one bulge.  So what causes the other bulge? 

Do you agree with the following or not?
Quote
On the opposite side of the earth, another tidal bulge also is created. This is because the centripetal force of the rotation of the earth and moon "throws" water to this side of the Earth to balance the center of mass.

It's an essential question. 
22
Science / Re: Direct Down Wind Faster Than The Wind
welcome to the eternal internet argument
23
Science / Re: The Tides ... Take 5
If there is no energy lost from bottom friction, what would happen?  Either in a real ocean or a magic canal? 
As always, you avoid simply answering this straight forward question.  The answer was mentioned in several books I linked to,  It's directly part of the argument you are putting forward, especially in regards to the hypothetical canal circling the earth.
And this new thing may or may not be connected to the canal problem.  Which you still have avoided answering.
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Science / Re: The Tides ... Take 5
There are certainly a lot of wrong things on the internet. 
It's determining the correct explanation and physics that is interesting.  Thanks to this never ending argument, I have stumbled across something remarkable, that has not come up yet. At least here.

And it's a real brain teaser.
25
Science / Re: The Tides ... Take 5
You actually seem to think friction can't slow tides, but you don't offer any physical explanation for what you think does happen. In your magic world where friction doesn't matter because of tidal forcing, where does the energy go? 
Quote
When tidal motions run into the shallow waters of the continental shelf, their rate of advance is reduced, energy accumulates in a smaller volume, and the rise and fall is amplified.
https://www.britannica.com/science/tide
Just ignoring the source, or saying "That is wrong" is not an argument.