Squares

General FreeBASIC programming questions.
albert
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Re: Squares

Postby albert » Jun 20, 2019 22:17

@Richard

He said the winds of 1/2 mph or less (8 1/2 inches per second ) , do nothing to the reflectivity of water..
A slight zephyr will momentarily disturb the reflectability..( slight gust for a moment of 1 mph or higher )

It takes a steady wind of about 1 mph , to distrub the waters reflectability ( make slightest ripples )
He said the ripples , might be a factor of the surface film of the water.. or elasticity of the waters surface.

@Dodicat
When you heat up a pan of water, the IR waves vibrate the water molecules to beyond their 500 MPH max speed and causes air pockets ( bubbles ) at the bottom of the pot..
When a boat propeller hits 500 mph it builds up air pockets around the blades and then the boat can't go any faster, cause it can't push any more water..

Like they have to carefully choose propeller diameters of air planes so as to keep the max tip speed below the speed of sound.

With speed boats , they have to carefully balance the diameter and blade pitch so the propeller won't exceed the 500 mph at max throttle.
Last edited by albert on Jun 20, 2019 22:39, edited 1 time in total.
Richard
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Re: Squares

Postby Richard » Jun 20, 2019 22:38

He did not write "do nothing to the reflectivity of water..".

He wrote; "This appearance Will not be affected by even a slight motion of the air, and a velocity of less than half a mile an hour (8½ in. per sec.) does not sensibly disturb the smoothness of the reflecting surface".

That does not mean a slight motion does not affect the surface, just that the change in reflective appearance is so small it cannot be sensed by the human eye.
albert
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Re: Squares

Postby albert » Jun 20, 2019 22:46

Thanks Richard... "Can't be sensed by the human eye.."

But when you drop a mass into water, the water can only support a certain mass per second..

If you exceed that mass per second , it builds up a pressure.

Since water is not compressible , that pressure causes a column to rise up.
That column falling back down causes the ripple or wave,

If the column rises up to a certain point , it will crest and fall over like a regular wave hitting the shore.
While also sending out a falling column wave.. So you get two waves out of a massive collision...

If an asteroid hits the water , that's 1,000 feet wide , it might cause a column to rise up 1,000 feet. ( might call it an incidental wave )
The rest of the water that didn't crest, falls back down and causes a "column falling" wave.)

When you do a "Cannon Ball" in the swimming pool ( curl up in a ball and drop in butt first ) , the incidental wave , is like 6 feet high and goes out in all different directions. The column falling wave is like 2 or 3 foot.. You get two waves..

You might call the column rising an "Incidental wave"
and the column falling , a "post incidental wave"
????

I think that the "incidental wave" is always bigger than the "post incidental wave"?
albert
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Location: California, USA

Re: Squares

Postby albert » Jun 21, 2019 2:42

@Richard
@Dodicat

Can you comment on my above post???

Maybe you know the Physics behind the "Incidental Wave" and "Post Incidental Wave" ?
Richard
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Re: Squares

Postby Richard » Jun 21, 2019 3:19

@Albert. You describe things happening that seem more imaginative than observational.
It does not happen like that on planet Earth. What planet are you on ?
dodicat
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Re: Squares

Postby dodicat » Jun 21, 2019 12:01

This is an important day on planet earth, the solstice.
It is an astronomical maximum which affects every species, especially the druids who, after witnessing sunrise at Stonehenge this morning, will now be guzzling gallons of beer.
srvaldez
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Re: Squares

Postby srvaldez » Jun 21, 2019 13:02

ahh, ice-cold beer :-)
albert
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Location: California, USA

Re: Squares

Postby albert » Jun 21, 2019 15:10

@Richard

How then , does a pebble cause a wave?

From my observations:

The pebble falling into the water , causes water to rise up , then the water that rose up , falls back down and causes a ripple to travel out.

The water rising up , you could call an "Incidental or Primary wave"
The water falling back down , you could call a "Post Incidental or Secondary wave"

I think the primary wave is always taller than the secondary wave. By an order of 2 or more times...
Last edited by albert on Jun 21, 2019 16:51, edited 1 time in total.
fxm
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Re: Squares

Postby fxm » Jun 21, 2019 16:03

More general note on the scientific literature

The best book I know about the amazing history of mathematics and physics:
    The Road to Reality: A Complete Guide to the Laws of the Universe
      by Roger Penrose
Downloadable pdf file
srvaldez
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Re: Squares

Postby srvaldez » Jun 21, 2019 16:27

Richard
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Location: Australia

Re: Squares

Postby Richard » Jun 21, 2019 17:41

Two hours past the winter solstice here, and it is 0°C. But the sky above is –27°C which explains why the wallabies have eaten their mid-winter feast of apples and moved in under the shed to await sunrise and the melting of the frost.

Albert wrote:How then , does a pebble cause a wave?
The mathematics is determined by the fluid dynamics, which in turn, is decided by the shape of the pebble. If you assume the pebble is a perfect sphere, then there will be at least three different wave systems generated. If you assume the pebble is an inverted cone you might get away with just two different wave systems. A long fusilla shaped pebble could generate just one wave system.
The resultant wave pattern is the sum of all the wave systems generated. It is also a function of the water depth and the speed of the pebble.
albert
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Re: Squares

Postby albert » Jun 21, 2019 17:46

Water can only absorb energy "me" Joules a second.

If the energy of the object falling into the water , exceeds "me" Joules , it causes a pressure to build up in the water.

Since the water can't compress under the pressure , the energy exceeding "me" Joules , causes water to rise up above the surface of the water.

That water rising up , is the "Incidental or Primary wave".

That primary wave then falls down ( collapses ) at the speed of gravity , and causes a ripple to travel out..
That ripple is the "Post Incidental or Secondary wave".

If I slowly push the fishing bobber up and down in the water , it won't make a wave , ( the water can absorb the energy .)
If i accelerate it to a certain velocity , the energy will exceed "me" Joules a second , and cause water to rise up above the surface. (primary wave.)

Water energy absorption , might be in Joules per square measure per second.?? measure being inches , feet , meters etc..


I think the formula for water collision , energy. Is E = mass * drag * velocity ^ 2
Where a perfect airfoil , of dimensions w , l ,h is formed to have the least possible resistance = drag 1
Every other object has ( drag 1 * ?? )


If you exceed "me" Joules per second , it causes a "primary wave" to pop up..

In this video you can clearly see the primary and secondary waves..https://www.youtube.com/watch?v=NF8aQHwcKN0
The "primary" wave is always several times higher than the "secondary" wave..

( off to sink me joules )
albert
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Re: Squares

Postby albert » Jun 21, 2019 20:45

In this video you can clearly see the primary and secondary waves..https://www.youtube.com/watch?v=NF8aQHwcKN0

The drop hits the water , and causes a primary wave

The primary wave , then collapses and creates a secondary wave.

The primary wave falling back into the void left behind by the droplet, causes a second primary wave , that then collapses to create another secondary wave.

So you get 2 primaries and 2 secondaries..

Collisions cause "Primary waves" , "Primaries" collapsing causes "Secondary waves"..

Watch the video!!!

Two waves coming together at a certain phase , will cause a collision and thus create a primary wave..

If i put my hand in the water, and move it up & down at a certain velocity , it will cause secondary waves without a primary.
A "Primary" or "Incidental" wave , requires a collision or certain energy per second..

So: i can slosh my hand around in the sink and create secondary waves.. Some of those secondary waves might collide and create some primaries..

That's my aim: To figure out , how to slosh the solid around , to cause it to form "Primary Waves" ( rogue waves )
albert
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Re: Squares

Postby albert » Jun 22, 2019 0:25

==============================================
Please read last two posts on previous page..
==============================================


When a "Secondary wave" , comes close to the shore.
The shallow depth and bottom resistance , cause the wave to slow down at the bottom while keeping the same speed or accelerating at the top.
This causes the wave to crest and fall over , making a tube...

Maybe this tube is the same as a "primary" wave?

The bottom slope per foot makes all the difference in the tube that forms.
One area might get 10 foot tubes , and 1 mile away they only get 2 foot tubes , it depends on the slope verses the depth..


If i move my hand through the water, at a certain velocity. it causes a pressure in front of my hand.
Since the water can't compress , it results in a mound of water building up , in front of my hand ..
Maybe the same thing as a "Primary" wave but without the height and crest.
That slight primary wave. then goes out as a secondary wave , a wake.

So:
You might have to classify "Primary" waves into two categories.
1 ) Collision Primaries.
2 ) Pressure primaries.
???

=======================================================================

In California , we have lots and lots of Mexicans , Hispanics..
In Spanish 10 is called Diaz
So 10 minutes = de-az me nuts
Got to wash the "az" off me nuts..
Richard
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Location: Australia

Re: Squares

Postby Richard » Jun 22, 2019 3:06

Albert wrote:I think the formula for water collision , energy. Is E = mass * drag *velocity ^ 2
Unfortunately Albert, all the terms you are using have been defined differently earlier.
kinetic energy; KE = ½ * mass * velocity^2. That must be the case. The derivative of kinetic energy is momentum, p = mass*velocity. So the square of velocity must have a ½ in the equation.
Obviously, what you are saying is that drag is always one half and never changes.

Albert wrote:Where a perfect airfoil , of dimensions w , l ,h is formed to have the least possible resistance = drag 1
Every other object has ( drag 1 * ?? )
But drag is already defined as a coefficient, without dimensions, that is a function of the shape.
A perfect shape has no drag, so drag coefficient = 0.

Albert wrote:If you exceed "me" Joules per second , it causes a "primary wave" to pop up..
There is no magical "me" threshold in physics. Outputs are proportional to inputs.
“Joules per second” is the rate of flow of energy, which is called power, the unit is the watt.

The structure of the equations and units in physics is a family tree. Every unit can be traced back through the tree to four original ancestors, the dimensions of; length, mass, time, and electric current.

What you are doing is making “postmodernist jargon soup” out of mathematics and physics.

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