I was actually honestly praising you there, as it's quite cool, but ok then
Zefan was being nice!misread you
I think me and tummy both got the wrong end of the stick there
I guess I should thank you then
(How much) does it matter when you weigh something?
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I think me and tummy both got the wrong end of the stick there
I guess I should thank you then
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“Recognize that the very molecules that make up your body, the atoms that construct the molecules, are traceable to the crucibles that were once the centers of high mass stars that exploded their chemically rich guts into the galaxy, enriching pristine gas clouds with the chemistry of life. So that we are all connected to each other biologically, to the earth chemically and to the rest of the universe atomically. That’s kinda cool! That makes me smile and I actually feel quite large at the end of that. It’s not that we are better than the universe, we are part of the universe. We are in the universe and the universe is in us.”
? Neil deGrasse Tyson
He has a way with words.
Indeed.
Interesting point
I think the universe strives for balance as a system - every action has an equal and opposite reaction, from the top down to the tiniest subatomic happenings creating antimatter to balance charges, however will never fully attain it. As there is a minimal amount of antimatter compared to matter itself - the fundamental balance. The only balanced universe could not exist, as matter and antimatter annihilate each other, leaving, well, pure energy. But then energy itself could manifest into another matter filled universe. An endless cycle. And I'm now straying into highly theoretical physics which I don't really understand, so if I get things wrong please don't jump at me Indeed he does.....
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I would too, but odd questions pop into my head and I like to have the answers to them even if they have no relevance to my life.
Indeed.
Interesting point
I won't jump at you, it is beyond me, my brother is the physicist not me......I'm more philosophical than scientific....
I do the imagining, he does the math to see if it is possible......so to speak.
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This! I always get random little ideas, and want to find the answers! That's why I do maths
I won't jump at you, it is beyond me, my brother is the physicist not me......I'm more philosophical that scientific....
I do the imagining, he does the math to see if it is possible......so to speak.
I'm more of a mathematician, but I love physics, as it's basically maths in application
However I do like to philosophise about things. You can't understand things truly unless you ask "why?"
In all seriousness though this is actually quite a simple question to answer, just need to use the gravitational equations any physics a-level student should know (or at least be able to use)
Remember mavity is a two way thing, the tide isn't just pulled by the moon, the moon is pulled by the tide, thankfully circular motion stops them meeting as having neither or both on this planet would not be good.
Average weight of human is 80kg (perhaps), just need to find out the weight of the moon, the distance (center to center then adjust by subtracting earths radius).
It really will be negligible as humans are so small, the only reason the tide is effected is because as a liquid it is in effect one huge thingy rather than lose individual water molecules. I doubt it would register on cooking scales.
Easiest thing to do would be to weigh something then wait 15 days and weight it again.
Remember mavity is a two way thing, the tide isn't just pulled by the moon, the moon is pulled by the tide, thankfully circular motion stops them meeting as having neither or both on this planet would not be good.
Average weight of human is 80kg (perhaps), just need to find out the weight of the moon, the distance (center to center then adjust by subtracting earths radius).
It really will be negligible as humans are so small, the only reason the tide is effected is because as a liquid it is in effect one huge thingy rather than lose individual water molecules. I doubt it would register on cooking scales.
Easiest thing to do would be to weigh something then wait 15 days and weight it again.
![[FnG]magnolia](/styles/overclockers/avatars/9.png){kind=avatar}
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[/URL]
He has a way with words.
He actually does.
The reasoning is sound. The magnitude of the change will be negligible. Assuming you can find the orbital radius of the Moon, and the radius of the Earth, it shouldn't take too long to work out how much your weight changes when the Moon is pulling directly upwards vs when it's pulling directly downwards. Take the orbits to be circular. I can't be bothered at this time of night though, so I'll just say I'm sure it's negligible.
For that matter, g varies with altitude, so g at sea level is different to that some distance up a mountain. It's greater towards the poles, as the Earth bulges in the middle. It'll also be slightly higher when you're standing on a denser area of the Earth. This effect isn't especially significant either.
It might be interesting to check whether variation across the Earth's surface (something like 1% iirc) is greater than the variation due to the Moon's location. I'm pretty sure the Moon will still look negligible, even in comparison to that fairly minor variation.
For that matter, g varies with altitude, so g at sea level is different to that some distance up a mountain. It's greater towards the poles, as the Earth bulges in the middle. It'll also be slightly higher when you're standing on a denser area of the Earth. This effect isn't especially significant either.
It might be interesting to check whether variation across the Earth's surface (something like 1% iirc) is greater than the variation due to the Moon's location. I'm pretty sure the Moon will still look negligible, even in comparison to that fairly minor variation.
Negligible yes, but still there
This is why we can never find the absolute mass of something, because, no matter where in the universe it is, it will still be affected by mavity of some sort
However we can get damn close!
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OH GOD I WISH WE HAD A FORUM HERE WHERE PEOPLE KNEW WHAT THEY WERE TALKING ABOUT INSTEAD OF "GOSH, HERE'S SOME IDEAS I HAVE THAT HAVE NO BASIS IN LITERALLY ANYTHING!".
So, to answer the question I think it's space demons mainly and those formulae we all learned at school with some other crap I read off the internet to bulk up my retort, with also and not to mangle English too much Carl to the ****** Sagan ****** Space Warrior Duded.
Does that answer your question OP?
So, to answer the question I think it's space demons mainly and those formulae we all learned at school with some other crap I read off the internet to bulk up my retort, with also and not to mangle English too much Carl to the ****** Sagan ****** Space Warrior Duded.
Does that answer your question OP?
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Conjecture and A Levels doesn't make for a great debate and certainly doesn't deliver an answer. As far as I know, there is no one here who is capable of both fielding and asking questions regarding the topic, in a any sense that is actually worth bothering with.
If this is just another 'Hey guys, physics, WAT?' post then great.
If this is just another 'Hey guys, physics, WAT?' post then great.
Mummy the scary man is scaring me.
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I actually liked Castiel's responses as I generally do. That doesn't mean that it's not a shame that we don't have more rounded and answerable posters here when it comes to situations exaclty like the OP.
[FnG]magnolia;21020963 said:
I certainly do not have the maths for it, but that doesn't mean you can't discuss it as a general point. Although we did move away from the OPs specific premise I agree.....probably because we didn't know but thought it was interesting to discuss a related philosophical point....
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