- #1
Jacinta
- 22
- 12
I mean it would be impossible for Earth to be fully spherical as it would be too bumpy to be a sphere shape.
If this is the case, why is Earth considered round?
If this is the case, why is Earth considered round?
'Cause it's close enough for government work. You do the math. Figure out the tallest mountain as a percentage of the radius of the Earth.Jacinta said:... why is Earth considered round?
Jacinta said:I mean it would be impossible for Earth to be fully spherical as it would be too bumpy to be a sphere shape.
If this is the case, why is Earth considered round?
phinds said:Oh, and by the way, it is NOT considered round by scientists when they are being precise. That's just a pop-science simplification.
CWatters said:Because the Earth spins the radius is about 13 miles greater at the equator than the poles.
CWatters said:Increases.
Jacinta said:I don't think this looks very spherical? Looks more like my cats chew toy.
Would you consider a billiard ball as being spherical? If so, if you were to scale the Earth down to the size of billiard ball, the roughness of it surface due to mountains a valleys would be less than the manufacturing tolerances for irregularities for a billiard ball. Even including the equatorial bulge leaves the Earth pretty close to that tolerance.Jacinta said:I mean it would be impossible for Earth to be fully spherical as it would be too bumpy to be a sphere shape.
If this is the case, why is Earth considered round?
I like Serena said:Indeed. That doesn't look spherical at all.
It looks more like a model of the Earth that a cat chewed on!
For reference, Earth actually looks like this:
http://stream1.gifsoup.com/view1/1210397/earth-o.gif
Janus said:Would you consider a billiard ball as being spherical? If so, if you were to scale the Earth down to the size of billiard ball, the roughness of it surface due to mountains a valleys would be less than the manufacturing tolerances for irregularities for a billiard ball. Even including the equatorial bulge leaves the Earth pretty close to that tolerance.
I like Serena said:
No, it's just standard pop-science. YOU do something about it if you actually imagine that you are going to change the culture of popular science reporting. Saying that popular science reporting is dumb is a tautology and a waste of breath.Jacinta said:But it's dumb, shouldn't scientists do something about this? A sphere is something you can roll around, I don't think you can roll around the Earth.
phinds said:No, it's just standard pop-science. YOU do something about it if you actually imagine that you are going to change the culture of popular science reporting. Saying that popular science reporting is dumb is a tautology and a waste of breath.
The Earth could roll if it had something to roll on. It's wobble would not be noticeable; it is way too small. It would roll better than a baseball or soccer ball.Jacinta said:Yes, because a billiard ball can roll around.
The Earth can't roll around but spin around, there is a difference.
Jacinta said:Interesting.
is not an image of the Earth as it is, but is an artificially created image intended to show something other than the Earth's physical shape
Jacinta said:If this is the case, why is Earth considered round?
Read http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htmJacinta said:I mean it would be impossible for Earth to be fully spherical as it would be too bumpy to be a sphere shape.
If this is the case, why is Earth considered round?
Yes, and not just modified but also deliberately exaggerated.CWatters said:Anyway its most likely an image of the Earth modified to show how gravity varies due to changes in density and the like.
A ball has a relatively thick tough outer surface under tension, with air inside under pressure that makes it approximately spherical.russ_watters said:The Earth could roll if it had something to roll on. It's wobble would not be noticeable; it is way too small. It would roll better than a baseball or soccer ball.
The seams on a baseball and soccer ball are proportionally taller than the Himalayas and deeper than the Mariana Trench - and also larger than the equatorial bulge of the Earth.Baluncore said:A ball has a relatively thick tough outer surface under tension, with air inside under pressure that makes it approximately spherical.
Agreed. This wasn't a statement about strength of materials, it was a statement about shape.The Earth has a very thin and fragile crust on a fluid mantle and a solid core. The crust floats on the surface and cannot handle tension. If you tried to roll the Earth on a flat surface it would immediately collapse, (like a fried egg), into a glob of red hot stainless steel, in the middle of a puddle of lava.
That's not how the term "sphere" is defined.Jacinta said:A sphere is something you can roll around, I don't think you can roll around the Earth.
This?Baluncore said:There are 2D figures and coins that are not round, but that have a constant diameter and can roll between two lines with fixed separation. In polar coordinates, the radius would be a constant term + odd harmonics.
Is there a 3D version of that? A non-spherical solid with constant diameter that fits neatly between two planes with fixed separation.
The outer core is liquid. The mantle is solid that “flows” on geologic time scales. The mantle also makes up the vast majority of the earth’s volume. This is verified readily by seismometry: the S waves radiated from earthquakes do not propagate through liquid, which would have easily observable effects of the mantle were liquid.Baluncore said:The Earth has a very thin and fragile crust on a fluid mantle and a solid core. The crust floats on the surface and cannot handle tension. If you tried to roll the Earth on a flat surface it would immediately collapse, (like a fried egg), into a glob of red hot stainless steel, in the middle of a puddle of lava.
The Earth is considered round because it is an oblate spheroid, meaning it is slightly flattened at the poles and bulging at the equator. This shape is a result of the Earth's rotation, which causes the centrifugal force to push outwards at the equator.
There are several pieces of evidence that support the roundness of Earth. One of the earliest pieces of evidence was the observation of ships disappearing over the horizon, which can only happen if the Earth is curved. Additionally, modern technology such as satellite imagery and space travel have provided concrete evidence of Earth's round shape.
The Earth's surface may appear bumpy due to mountains, valleys, and other geological features. However, these bumps are relatively small compared to the overall size of the Earth and do not affect its overall round shape.
No, Earth is not a perfect sphere. As mentioned earlier, it is an oblate spheroid, meaning it is slightly flattened at the poles and bulging at the equator. This is due to the Earth's rotation and the centrifugal force it creates.
Yes, the round shape of Earth has a significant impact on our daily lives. It affects the Earth's rotation, which creates day and night, and also influences the Earth's climate and weather patterns. Additionally, the round shape of Earth allows for the existence of life as we know it, as it provides a stable gravitational pull and atmosphere.