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what is the effect of human population growth on the earth's mass?

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Fritzo said:
If everyone moved to one side of the planet, it could affect the Earth's tilt a bit 🙂. Otherwise, we're all made of material that's already here. No mass increase. In fact, we're using resources and burning fuels, which is taking away from the earth's mass if the gases it causes bleed off into space.

On a side note, meteorites add roughly 1 million tons to the Earth's mass every year.
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But what about the nukes we set off to prevent them from destroying earth? :awe:
 
First, Even if every human that is currently alive on the earth today were to suddenly disappear, the mass of the earth would be relatively the same. The weight of a human to the earth is like the weight of an atom to a human.

Second, What do you mean by "The mass of the earth." Do you mean "The mass of all matter in the atmosphere that is not currently a part of some living organism" or do you mean "The mass of all matter that is in the earths atmosphere." If it is the first, then the answer is "The mass of the earth itself has decreased while the mass of living matter has increased." (I'm not completely sure about that). if it is the second the answer is "The mass of the earth has not changed." It could never be "The mass of the earth has increased." That is retarded.
 
Obviously it has no effect. Gains in human mass simply come from displacing animal and plant mass and taking more mass from water and air. Humans are made of mostly water and hydrocarbons. The carbon for hydrocarbons ultimately comes from the carbon dioxide in the air. Also, mount Everest weighs 3.041409x10^15kg. All humans put together probably weight about 4x10^11kg. So a single mountain weighs more than all humans.
 
vi edit said:
Question for those smarter than me since my high school physics was a good 15 years ago....

What's the net effect on "mass" with things like combustion engines that you put a hundred pounds worth of fuel into and it converts a lot of that into energy but some of it into solid and gas exhaust...but not all of it.

Or even human bodies where we may consume 10+ pounds of food and water a day but only excrete a small percentage of that?

Isn't there some loss in converting that mass into energy?

Or what about cremating bodies?

Are these all still net zero conversions?
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These are all net-zero conversions because we are not converting mass to energy... except in nuclear reactors.

We are not nuclear reactors.

We convert through chemical reactions.

Most of what we consume is made of water, we excrete a lot more liquid than you think. Every breath takes water and we push water out of our skin all the time.
 
vi edit said:
Question for those smarter than me since my high school physics was a good 15 years ago....

What's the net effect on "mass" with things like combustion engines that you put a hundred pounds worth of fuel into and it converts a lot of that into energy but some of it into solid and gas exhaust...but not all of it.

Or even human bodies where we may consume 10+ pounds of food and water a day but only excrete a small percentage of that?

Isn't there some loss in converting that mass into energy?

Or what about cremating bodies?

Are these all still net zero conversions?
Click to expand...

Humans do not convert mass into energy. Nuclear fission and fusion do. All humans do is take something in a higher energy state, and chemically change it into something in a lower energy state and use the energy released from that process. It is much akin to going around and throwing rocks off of cliffs, you release energy in the process, but the energy was already stored by the very presence of the bolder on a cliff.

Plants are interesting because they actually do take low energy state compounds and convert them to compounds with higher energy states by using photosynthesis. They do this so they can have food for the winter/night.
 
MotF Bane said:
If we placed BBYT and a certain 420 poster from P&N into a paper bag together, do you suppose either of them would ever find their way out?
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I suppose they wouldn't even be able to find each other in said bag. They surely wouldn't find their way out of the bag even if it were open and you held said bag upside down, shaking it vigorously.
 
vi edit said:
Question for those smarter than me since my high school physics was a good 15 years ago....

What's the net effect on "mass" with things like combustion engines that you put a hundred pounds worth of fuel into and it converts a lot of that into energy but some of it into solid and gas exhaust...but not all of it.

Or even human bodies where we may consume 10+ pounds of food and water a day but only excrete a small percentage of that?

Isn't there some loss in converting that mass into energy?

Or what about cremating bodies?

Are these all still net zero conversions?
Click to expand...
Burning of anything causes a tiny loss of mass due radiative energy losses into outer space and the fact that e=mc^2.

If you consume 10lbs of food and water a day, I guarantee you will excrete 9.9999lbs of matter a day. Exhaust air actually has a substantial amount of weight and a lot of water vapor is lost through skin and breathing. The same is true for things like cars.
 
DixyCrat said:
These are all net-zero conversions because we are not converting mass to energy... except in nuclear reactors.

We are not nuclear reactors.

We convert through chemical reactions.
Click to expand...
Energy in itself has mass. So a compressed spring has slightly more mass than an uncompressed spring in accordance to m = e/c^2. So, chemical reactions do actually result in a slight loss of mass even though they are non-nuclear. The mass loss is accounted for due to heat and photon emissions.
 
Cogman said:
Humans do not convert mass into energy. Nuclear fission and fusion do. All humans do is take something in a higher energy state, and chemically change it into something in a lower energy state and use the energy released from that process. It is much akin to going around and throwing rocks off of cliffs, you release energy in the process, but the energy was already stored by the very presence of the bolder on a cliff.

Plants are interesting because they actually do take low energy state compounds and convert them to compounds with higher energy states by using photosynthesis. They do this so they can have food for the winter/night.
Click to expand...
Mass is energy though. 😉

I seem to recall reading somewhere that converting graphite into diamond will result in a higher mass, as the diamond's structure contains more potential energy. However, this mass difference is very small compared to what goes on in a nuclear reaction.
 
Cogman said:
Humans do not convert mass into energy. Nuclear fission and fusion do. All humans do is take something in a higher energy state, and chemically change it into something in a lower energy state and use the energy released from that process. It is much akin to going around and throwing rocks off of cliffs, you release energy in the process, but the energy was already stored by the very presence of the bolder on a cliff.
Click to expand...

Ok now very faint memories of the kreb cycle are staring to wonder back into my brain...
 
Even if you did somehow magically add to Earth's mass, by say for example taking a dump on the moon and throwing it at the earth, being born and raised on the moon and eating moon rocks for sustenance (nothing from Earth for you, moonling)

Or let's just say the OP is a moonling and visits Earth. Oh but I repeat myself.


Did you get it yet? What do I mean by repeat myself?


Earth's gravitational field would hold that much less mass of air.

It would be displaced.
Into space,
like the one between your ears.
 
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How did this thread get so many replies with such an idiotic title? Oh... I guess I'm not the only one goaded into responding thusly.
 
vi edit said:
Question for those smarter than me since my high school physics was a good 15 years ago....

What's the net effect on "mass" with things like combustion engines that you put a hundred pounds worth of fuel into and it converts a lot of that into energy but some of it into solid and gas exhaust...but not all of it.

Or even human bodies where we may consume 10+ pounds of food and water a day but only excrete a small percentage of that?

Isn't there some loss in converting that mass into energy?

Or what about cremating bodies?

Are these all still net zero conversions?
Click to expand...

Most of that is easily explained by entropy (basically losses in heat).

ICE are very inefficient (only convert like maybe 30 something percent of the energy in gasoline), a lot of it is lost as heat.

Humans also lose heat (although, in a sense, we also store it in that we have a pretty high body temperature), and it takes quite a bit of energy to just function, and remember your body is always functioning, it doesn't shut off. We also tend to store excess energy (calories).

Cremating bodies, well, there's a lot lost to heat there obviously (which is the point).
 
OPs post wasn't a jubilee of sorts. Which means it may be serious. If so I think I have the first person to place on my ignore list 😀
 
vi edit said:
I guess that's really my question...does heat have mass? Or is that mass that is truly "gone"?
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Heat is energy. Basically, it being gone depends on the system. Since earth isn't a closed system, we don't really lose as we get energy from the sun.

Thermodynamics basically says that since some is lost as heat energy, that over time it would add up, where if all were converted the heat would kill the system.
 
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Now if we all just flew away to another Planet, then it might make a significant difference. Or, if we began bringing Resources from Asteroids/Moons/Planets, eventually we'd have Mass Pollution.

edit-Just to clarify, for all Intents and purposes, we are Part of the Earth's Mass. Until we leave anyway.
 
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