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If all the matter on earth were reassembled uniformly so as to possess a (virtually) perfectly smooth surface (with densities changing as is necessary for the planet's stability, but otherwise also uniform), how would the size and volume change? Furthermore, how apparent would the curve of the planet's surface be from an average human's perspective?

Additional thought experiment: 
What is the farthest distance two points on the surface of the sphere could be from each other, before two average humans holding two ends of a long cellulose fiber rope located on these points would not be able to pull it taut?

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51 minutes ago, Anchovyforestbane said:

If all the matter on earth were reassembled uniformly so as to possess a (virtually) perfectly smooth surface (with densities changing as is necessary for the planet's stability, but otherwise also uniform), how would the size and volume change? Furthermore, how apparent would the curve of the planet's surface be from an average human's perspective?

Additional thought experiment: 
What is the farthest distance two points on the surface of the sphere could be from each other, before two average humans holding two ends of a long cellulose fiber rope located on these points would not be able to pull it taut?

The answer to the first question is '0'.

There's not enough information provided to answer the 2nd. question but I can fix it for you.

How many miles between two 6 foot tall people for them to see each other's heads if atmospheric conditions for viewing are perfect?

6 miles

Bonus question: What kind of an a-s would want to invent a tail on Mars that can be seen by him and his daddy? Twice!

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On 10/23/2020 at 7:37 PM, montgomery said:

The answer to the first question is '0'.

With the vastly different volume densities of different materials, from air, to water, to diamond; there should be no difference should these discrepancies be alleviated? Elaborate. 

 

 

On 10/23/2020 at 7:37 PM, montgomery said:

Bonus question: What kind of an a-s would want to invent a tail on Mars that can be seen by him and his daddy? Twice!

Disregarding my lack of understanding of whatever lingo you're using here:
How amusing, your talent of obstinacy is as nauseating as ever; enough so to pollute completely unrelated topics with your pigheaded calumny.
If you've got some issue with me, take it to PMs. Leave the science threads for science.

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11 minutes ago, Anchovyforestbane said:



 

 

Disregarding my lack of understanding of whatever lingo you're using here:
How amusing, your talent of obstinacy is as nauseating as ever; enough so to pollute completely unrelated topics with your pigheaded calumny.
If you've got some issue with me, take it to PMs. Leave the science threads for science.

I'm not going to disregard anything for your pleasure. Why did you make up the story for a second time? The first time could be excused because you failed to think of a natural explanation, and that's common to most Americans. It's the reason why we have dingbats like Thoth on a science forum. But the second time is inexcuable because you had to fabricate a lie and say you saw the tail again. Had you actually have seen a tail on Mars the entire scientific community which is involved with the applicable science would be asking big questions. AND THEY'RE NOT! 

Smarten the fuk up and try growing fkng up a bit!

 

With the vastly different volume densities of different materials, from air, to water, to diamond; there should be no difference should these discrepancies be alleviated? Elaborate. [/quote]

best to put the question down to ignorant nonsense and move on. Spend your time with science that makes some sense.

And maybe you could consider thanking me for helping you to grow up a little faster than you ordinarily would?

This loony bin forum needs a lot more tough love of the sort only I am offering so far.

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24 minutes ago, montgomery said:

I'm not going to disregard anything for your pleasure. Why did you make up the story for a second time? The first time could be excused because you failed to think of a natural explanation, and that's common to most Americans. It's the reason why we have dingbats like Thoth on a science forum. But the second time is inexcuable because you had to fabricate a lie and say you saw the tail again. Had you actually have seen a tail on Mars the entire scientific community which is involved with the applicable science would be asking big questions. AND THEY'RE NOT! 

Smarten the fuk up and try growing fkng up a bit!

 

With the vastly different volume densities of different materials, from air, to water, to diamond; there should be no difference should these discrepancies be alleviated? Elaborate. [/quote]

best to put the question down to ignorant nonsense and move on. Spend your time with science that makes some sense.

And maybe you could consider thanking me for helping you to grow up a little faster than you ordinarily would?

This loony bin forum needs a lot more tough love of the sort only I am offering so far.

Your discourteous little tirade there has been reported.
At first I thought you were simply ignorant and petty; an angsty teenager, perhaps. 
But in your arrogance you've revealed yourself to be self-righteous and manipulative. 
Quite frankly you should be ashamed of yourself. 
If your ready to contribute to scientific discussion on this science forum, than my ears are open. 
Until then, if snide disrespect and self-centered manipulation is all you have to say to me, then I have nothing left to say to you except to act your age.

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13 hours ago, Anchovyforestbane said:

Your discourteous little tirade there has been reported.
At first I thought you were simply ignorant and petty; an angsty teenager, perhaps. 
But in your arrogance you've revealed yourself to be self-righteous and manipulative. 
Quite frankly you should be ashamed of yourself. 
If your ready to contribute to scientific discussion on this science forum, than my ears are open. 
Until then, if snide disrespect and self-centered manipulation is all you have to say to me, then I have nothing left to say to you except to act your age.

Ask  mommy moderator to make me go away then! They've already tried that twice and now they are coming to understand that I don't give a fuk. If they want to lose their most sane and prolic poster then maybe you'll get your wish.

And won't that work out well for you and your cousin Thoth! You can make up tails on Mars and other **** and be completely undisturbed! 

Edited by OceanBreeze
removed abusive content
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On 10/28/2020 at 3:44 PM, montgomery said:

Ask  mommy moderator to make me go away then! They've already tried that twice and now they are coming to understand that I don't give a fuk. If they want to lose their most sane and prolic poster then maybe you'll get your wish.

And won't that work out well for you and your cousin Thoth! You can make up tails on Mars and other **** and be completely undisturbed! 

Gee, I can't possibly imagine their motive for that.

The fact that you find it to be something to brag about, flawlessly displays the irony that your self-perceived sanity is almost as intense as your lack thereof.

Edited by Anchovyforestbane
found better wording
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14 hours ago, Anchovyforestbane said:

With the vastly different volume densities of different materials, from air, to water, to diamond; there should be no difference should these discrepancies be alleviated? Elaborate. 

 

 

Disregarding my lack of understanding of whatever lingo you're using here:
How amusing, your talent of obstinacy is as nauseating as ever; enough so to pollute completely unrelated topics with your pigheaded calumny.
If you've got some issue with me, take it to PMs. Leave the science threads for science.

"If you've got some issue with me, take it to PMs. Leave the science threads for science"

Exactly right.

 

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13 hours ago, montgomery said:

Ask  mommy moderator to make me go away then! They've already tried that twice and now they are coming to understand that I don't give a fuk. If they want to lose their most sane and prolic poster then maybe you'll get your wish.

And won't that work out well for you and your cousin Thoth! You can make up tails on Mars and other **** and be completely undisturbed! 

Three strikes you're out Monty and that is the only reason why I am not suspending you for a third time. You can be a reasonably intelligent poster if you want, Monty. Why not give that a try for a change?

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On 10/28/2020 at 4:44 PM, montgomery said:

Ask  mommy moderator to make me go away then! They've already tried that twice and now they are coming to understand that I don't give a fuk. If they want to lose their most sane and prolic poster then maybe you'll get your wish.

And won't that work out well for you and your cousin Thoth! You can make up tails on Mars and other **** and be completely undisturbed! 

Don't make me have to sacrifice you to Satan!

tumblr-m4sqwh-XIx41qlmgy7o1-500.jpg

Edited by VictorMedvil
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On 10/28/2020 at 2:27 PM, montgomery said:

I'm not going to disregard anything for your pleasure. Why did you make up the story for a second time? The first time could be excused because you failed to think of a natural explanation, and that's common to most Americans. It's the reason why we have dingbats like Thoth on a science forum. But the second time is inexcuable because you had to fabricate a lie and say you saw the tail again. Had you actually have seen a tail on Mars the entire scientific community which is involved with the applicable science would be asking big questions. AND THEY'RE NOT! 

 

That is funny coming from someone who don't even know the definition of science.

Science is a systematic method of continuing investigation, based on observation, scientific hypothesis testing, measurement, experimentation, and theory building, which leads to explanations of natural phenomena, processes, or objects, that are open to further testing, revision, and falsification, and while not 'believed in' through faith are accepted or rejected on the basis of scientific evidence."

 

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Most of the matter that makes up the earth (rocks, water etc.) generally do not change their density all that much (with pressure for example), So a uniform distribution of that matter would not really make much difference to the volume of the earth. 

As for how smooth, it is already amazingly smooth, even with the big bumps on it like Mt Everest and deep ocean trenches, it is still amazingly smooth.

Imagine a Que ball off a pool table, very round and very smooth right, the earth is much smoother than that que ball.  Or if you scaled the que ball to the same of the earth it would be really lumpy compared to the earth.. 

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29 minutes ago, Mutex said:

Most of the matter that makes up the earth (rocks, water etc.) generally do not change their density all that much (with pressure for example), So a uniform distribution of that matter would not really make much difference to the volume of the earth. 

You seem to be thinking of volume in relation to mass; I'm talking about volume in relation to geometry. In other words, you are correct that the resulting figure would have the same matter-containing capacity, but I'm talking about the amount of space the figure occupies. 
 

35 minutes ago, Mutex said:

Imagine a Que ball off a pool table, very round and very smooth right, the earth is much smoother than that que ball.  Or if you scaled the que ball to the same of the earth it would be really lumpy compared to the earth.. 

That depends on how you define smooth. If the earth were queball-sized relative to you, the surface would indeed feel smoother than an earth-sized queball. However, its macroscopic topology would not be nearly as uniform as that of the queball; visually speaking, it would look lumpier. 

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1 hour ago, Anchovyforestbane said:

That depends on how you define smooth. If the earth were queball-sized relative to you, the surface would indeed feel smoother than an earth-sized queball. However, its macroscopic topology would not be nearly as uniform as that of the queball; visually speaking, it would look lumpier. 

According to this article, the earth has similar roundness to a billiard ball, but is not as smooth.

Roundness: According to the World Pool-Billiard Association, “All balls must be composed of cast phenolic resin plastic and measure 2 1/4 (±.005) inches [5.715 cm (± .127 mm)] in diameter”.

Earth’s equatorial diameter is 7,926 miles (12,756 km), but from pole to pole, the diameter is 7,898 miles (12,714 km) – a difference of only 28 miles (42 km). If we take the bigger diameter and shrink it down, the difference would be 0.0049 inches (0.0125 mm). If we take the smaller diameter, the difference would be very slightly bigger, but almost the same. So yes, the Earth is as round as a billiard ball.

As for smoothness: According to a 2013 study titled “Feeling Small: Exploring the Tactile Perception Limits” published on Nature, a human finger can feel wrinkles as small as 10nm (nanometers), or 0.00001 millimeters, demonstrating that human tactile discrimination extends to the nanoscale. So, if the Earth were shrunk down to the size of a billiard ball, you would definitely feel Mount Everest, which would be 0.04 millimeters high. That would be similar in smoothness to a billiard ball and covered its surface with very fine sandpaper of P360 grit, particle size of 0.0462 mm. (0.002 in)

So, it seems the billiard ball-sized earth would not feel or look as smooth as an actual billiard ball although it is as round. At least that is so according to the linked article. What do you think?

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1 hour ago, OceanBreeze said:

According to this article, the earth has similar roundness to a billiard ball, but is not as smooth.

Roundness: According to the World Pool-Billiard Association, “All balls must be composed of cast phenolic resin plastic and measure 2 1/4 (±.005) inches [5.715 cm (± .127 mm)] in diameter”.

Earth’s equatorial diameter is 7,926 miles (12,756 km), but from pole to pole, the diameter is 7,898 miles (12,714 km) – a difference of only 28 miles (42 km). If we take the bigger diameter and shrink it down, the difference would be 0.0049 inches (0.0125 mm). If we take the smaller diameter, the difference would be very slightly bigger, but almost the same. So yes, the Earth is as round as a billiard ball.

As for smoothness: According to a 2013 study titled “Feeling Small: Exploring the Tactile Perception Limits” published on Nature, a human finger can feel wrinkles as small as 10nm (nanometers), or 0.00001 millimeters, demonstrating that human tactile discrimination extends to the nanoscale. So, if the Earth were shrunk down to the size of a billiard ball, you would definitely feel Mount Everest, which would be 0.04 millimeters high. That would be similar in smoothness to a billiard ball and covered its surface with very fine sandpaper of P360 grit, particle size of 0.0462 mm. (0.002 in)

So, it seems the billiard ball-sized earth would not feel or look as smooth as an actual billiard ball although it is as round. At least that is so according to the linked article. What do you think?

I see, so possibly quite the reverse of what I've proposed. There are a couple of things to think about here.
The first is that the forces at play in the Earth rotating around its axis do have measurable effects on the perceived "roundness". If we were to freeze time in any such instance and smooth out the Earth's "wrinkles", it would be more ellipsoidal than spherical, and even then not perfectly so due to any nonuniformity within the Earth's mantle. Say we were able to measure directly through the Earth from one point straight to its antipode; the diameter would be notably different depending on the given point. 
The second, is that in sandpaper the fluctuations in surface area or more or less uniform. Macroscopically speaking the peaks and trophs are generally equidistant. This would not be so on Earth, do to the geochemical and meteorological effects liquid water has had on the rock (such as weathering, erosion, etc.), not to mention the effects of volcanic activity. Some peaks are peaks among peaks, and other trophs are trophs among trophs; that is to say, there is much more variation, not all mountains are Mount Everest. I propose that, due to this effect, the perceived "roughness" would resemble less what one would traditionally consider roughness, and more resemble an exaggeration to the aforementioned lack of roundness. 
What are your thoughts on this?

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7 hours ago, Anchovyforestbane said:

I see, so possibly quite the reverse of what I've proposed. There are a couple of things to think about here.
The first is that the forces at play in the Earth rotating around its axis do have measurable effects on the perceived "roundness". If we were to freeze time in any such instance and smooth out the Earth's "wrinkles", it would be more ellipsoidal than spherical, and even then not perfectly so due to any nonuniformity within the Earth's mantle. Say we were able to measure directly through the Earth from one point straight to its antipode; the diameter would be notably different depending on the given point. 
The second, is that in sandpaper the fluctuations in surface area or more or less uniform. Macroscopically speaking the peaks and trophs are generally equidistant. This would not be so on Earth, do to the geochemical and meteorological effects liquid water has had on the rock (such as weathering, erosion, etc.), not to mention the effects of volcanic activity. Some peaks are peaks among peaks, and other trophs are trophs among trophs; that is to say, there is much more variation, not all mountains are Mount Everest. I propose that, due to this effect, the perceived "roughness" would resemble less what one would traditionally consider roughness, and more resemble an exaggeration to the aforementioned lack of roundness. 
What are your thoughts on this?

I think there is an important distinction to be made between roundness, which refers to the overall shape, and smoothness which refers to the surface roughness. These are two separate specifications which should not be confused with one another. If we were discussing a cubic shape instead of a spherical one, I’m sure there would be no confusion between shape and surface roughness, but when it comes to a sphere there does seem to be some interaction between shape and roughness.

As your post shows, the issue can be best resolved by having very clear definitions for these two specifications to avoid confusing them.

Here is yet another source which does make this distinction between roundness and smoothness:

Smoothness: “The highest point on earth is Mount Everest, which is about 29,000 feet above sea level; and the lowest point (in the earth’s crust) is Mariana’s Trench, which is about 36,000 feet below sea level. The larger number (36,000 feet) corresponds to about 1700 parts per million (0.17%) as compared to the average radius of the Earth (about 4000 miles). The largest peak or trench for all of the balls I tested was about 3 microns (for the Elephant Practice Ball). This corresponds to about 100 parts per million (0.01%) as compared to the radius of a pool ball (1 1/8 inch). Therefore, it would appear that a pool ball (even the worst one tested) is much smoother than the Earth would be if it were shrunk down to the size of a pool ball”

“However, the Earth is actually much smoother than the numbers imply over most of its surface. A 1x1 millimeter area on a pool ball (the physical size of the images) corresponds to about a 140x140 mile area on the Earth. Such a small area certainly doesn’t include things like Mount Everest and Mariana’s Trench in the same locale. And in many places, especially places like Louisiana, where I grew up, the Earth’s surface is very flat and smooth over this area size. Therefore, much of the Earth’s surface would be much smoother than a pool ball if it were shrunk down to the same size”

Roundness: “Regardless, the Earth would make a terrible pool ball. Not only would it have a few extreme peaks and trenches still larger than typical pool-ball surface features, the shrunken-Earth ball would also be terribly non-round compared to high-quality pool balls. The diameter at the equator (which is larger due to the rotation of the Earth) is 27 miles greater than the diameter at the poles. That would correspond to a pool ball diameter variance of about 7 thousandths of an inch. Typical new and high-quality pool balls are much rounder than that, usually within 1 thousandth of an inch”

My conclusion:  The claim that the earth is as smooth as a billiard ball is false and it also is not as round. But I have come across still other online sources that disagree and these seem to be based mainly on differences in definitions.

 

 

 

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