Acceleration due to gravity vs. sunlight

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1eye
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Acceleration due to gravity vs. sunlight

Post by 1eye »

Wikipedia wrote:Latitude
The differences of Earth's gravity around the Antarctic continent.

At latitudes nearer the Equator, the inertia produced by Earth's rotation is stronger than at polar latitudes. This counteracts the Earth's gravity to a small degree – up to a maximum of 0.3% at the Equator – reducing the downward acceleration of falling objects.

The second major cause for the difference in gravity at different latitudes is that the Earth's equatorial bulge (itself also caused by inertia) causes objects at the Equator to be farther from the planet's centre than objects at the poles. Because the force due to gravitational attraction between two bodies (the Earth and the object being weighed) varies inversely with the square of the distance between them, an object at the Equator experiences a weaker gravitational pull than an object at the poles.

In combination, the equatorial bulge and the effects of the Earth's inertia mean that sea-level gravitational acceleration increases from about 9.780 m·s−2 at the Equator to about 9.832 m·s−2 at the poles, so an object will weigh about 0.5% more at the poles than at the Equator.[3][4]

The same two factors influence the direction of the effective gravity. Anywhere on Earth away from the Equator or poles, effective gravity points not exactly toward the centre of the Earth, but rather perpendicular to the surface of the geoid, which, due to the flattened shape of the Earth, is somewhat toward the opposite pole. About half of the deflection is due to inertia, and half because the extra mass around the Equator causes a change in the direction of the true gravitational force relative to what it would be on a spherical Earth.
Altitude
The graph shows the variation in gravity relative to the height of an object

Gravity decreases with altitude, since greater altitude means greater distance from the Earth's centre. All other things being equal, an increase in altitude from sea level to the top of Mount Everest (8,848 metres) causes a weight decrease of about 0.28%. (An additional factor affecting apparent weight is the decrease in air density at altitude, which lessens an object's buoyancy.[5]) It is a common misconception that astronauts in orbit are weightless because they have flown high enough to "escape" the Earth's gravity. In fact, at an altitude of 400 kilometres (250 miles), equivalent to a typical orbit of the Space Shuttle, gravity is still nearly 90% as strong as at the Earth's surface, and weightlessness actually occurs because orbiting objects are in free-fall.[6]
Also:
Wikipedia wrote:Comparative gravities in various cities around the world

The table below shows the gravitational acceleration in various cities around the world;[8] amongst these cities, it is lowest in Mexico City (9.779 m/s2) and highest in Oslo (Norway) and Helsinki (Finland) (9.819 m/s2).
[hide]Location Acceleration in m/s2
Amsterdam 9.813
Athens 9.800
Auckland 9.799
Bangkok 9.783
Brussels 9.811
Buenos Aires 9.797
Calcutta 9.788
Cape Town 9.796
Chicago 9.803
Copenhagen 9.815
Frankfurt 9.810
Havana 9.788
Helsinki 9.819
Istanbul 9.808
Jakarta 9.781
Kuwait 9.793
Lisbon 9.801
London 9.812
Los Angeles 9.796
Madrid 9.800
Manila 9.784
Mexico City 9.779
Montréal 9.789
New York City 9.802
Nicosia 9.797
Oslo 9.819
Ottawa 9.806
Paris 9.809
Rio de Janeiro 9.788
Rome 9.803
San Francisco 9.800
Singapore 9.781
Skopje 9.804
Stockholm 9.818
Sydney 9.797
Taipei 9.790
Tokyo 9.798
Vancouver 9.809
Washington, D.C. 9.801
Wellington 9.803
Zurich 9.807
I wonder how the strength of this effect compares with incident sunlight, when disease incidence is concerned? I am still talking about gravity's effect on reflux (again).
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Billmeik
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Re: Acceleration due to gravity vs. sunlight

Post by Billmeik »

not bad.Magnetism changes too as you get closer to the poles(I think)

Gravity wouldn't effect the supine position.
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Re: Acceleration due to gravity vs. sunlight

Post by 1eye »

I must admit I have not thought it through to see if incidence follows higher gravity or lower...
Gravity wouldn't effect the supine position.
Unless there was low flow in jugulars due to stenosis, and in absence of gravity bad becomes worse, i.e., higher incidence follows lower gravity (also less force to counteract reflux, in upright).
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Re: Acceleration due to gravity vs. sunlight

Post by Cece »

Gravity would still act on us when we are lying down. It wouldn't help blood outflow the way it does when we are standing. It could hinder if it is a weak force pulling blood flow towards the back wall of the vein instead of down through the veins. Weakly though. Interesting, 1eye. It might be too hot outside for me to think CCSVI! And it is rarely too hot for me to think CCSVI. :wink:
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Re: Acceleration due to gravity vs. sunlight

Post by 1eye »

Gravity seems to be weakest at the equator. That would make weaker gravity coincide with lower incidence of "MS". So more gravity-assisted outflow, or reduction of reflux would be associated with higher levels of disease. Not a sensible theory after all; excepting when you consider gravity's effect on cerebral venous pressure. Above the neck, in a higher gravity, the tendency to stretch veins would be greater. More collagen?

The gravity difference is minimal (0.41 %) compared to the variation in disease incidence. No, I think this baby should be thrown out with the bathwater.

The incidence variation should be the same order of magnitude, or closer, to the size of whatever variation, in germ incidence/susceptibility, or environment, or genetic types, is associated with it.
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Re: Acceleration due to gravity vs. sunlight

Post by CureIous »

As one of the few treated people who experienced sudden gravity changes while skydiving, without any valves to mitigate things, I can tell you it was very very noticeable. Felt like my head was going to explode. I could feel the veins bulging on the way down. My neck veins hurt for awile afterwards. Stent locations were throbbing.

No long or short term effects other than that, would highly recc. NOT doing that, however it really got me to thinking a lot, about how I always feel better upon waking if not sleeping flat, those veins are wide open now, nothing to impede flow either direction except gravity, gravity is my friend, we were having a beer last night, he was distraught because he felt I took him for granted all those years.

Now, I pay attention to him and try to use him for my benefit, he doesn't mind though, thats just how gravity is. Its 100 here, humid like Florida, this is the bad time when I get sleepy, groggy and suffer from CRS. Instead because gravity became my friend I run constantly.

Lets all buy gravity a beer next time we see him. He gets such a bad rap sometimes.
RRMS Dx'd 2007, first episode 2004. Bilateral stent placement, 3 on left, 1 stent on right, at Stanford August 2009. Watch my operation video: http://www.youtube.com/watch?v=cwc6QlLVtko, Virtually symptom free since, no relap
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