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Adding mass to Earth

  1. Apr 12, 2013 #1
    so i was thinking in the future all our resources would be depleted but we would harvest other planets for metals such as chrome aluminium titanium and so forth and maybe even iron.
    And we all know the more mass the planet has the higher the gravitational pull.
    so how much mass/resources can we import to earth without it interfering with the g ?
    and would we notice a small change from for instance 9.81 to 10.0 or 11.0?
  2. jcsd
  3. Apr 12, 2013 #2
    I really doubt it. We'd have to bring around 1.134e23 kg of material from outer space just for g to increase to 10. That's not to say it couldn't happen, but I really doubt it would get to that point.
  4. Apr 12, 2013 #3
    could happen, would we notice 10.0 g or 11.0 g?
  5. Apr 12, 2013 #4
    I don't think 10 g would make a massive difference, g is occasionally rounded to that anyways.

    11 would probably be a bigger difference, but we'd have to bring home about 7.219e23 kg of material. The effects on the earth of bringing that much mass home would probably have killed us long before we noticed the difference in both cases.
  6. Apr 12, 2013 #5
    killed us how? and what are the effect of living in higher g ? bone aches?
  7. Apr 12, 2013 #6


    Staff: Mentor

    you can determine this yourself using the g=GM/r^2 with r=radius of the Earth and G the gravitational constant and M the mass of the Earth. From that you can M in terms of g: M=g*r^2/G so basically going from 9.81 to 9.82 is 0.01*r^2/G mass increase.

    R = 6,371 km = 6.371E+6 m
    G = 6.67384E-11
    M = 6.081902e+21 kg for going from 9.81 to 9.82 m/s^2

    current mass of Earth = 5.97219E+24 kilograms
  8. Apr 12, 2013 #7
    I suppose so, though I'm thinking more in terms of volume. There isn't enough room on earth for that kind of mass without completely destroying natural life as we know it. Keep in mind, the amount we have to import is only a decimal place or so away from the mass of the earth; we'd be crushed.
  9. Apr 12, 2013 #8
    thanks jedish but im more concerned about the effects it has on mankind.
  10. Apr 12, 2013 #9
    i kinda thought of higher g would be same as gaining a lot of weight and feeling you are heavy as you walk for instance im like 115kg so i feel heavy cant really move around much but i do weighttrain a lot of it is muslces. but i still feel a bit immobile.

    although there is a flip side to that story and that is exporting minerals from earth and having a lower g, that would be great we could jump higher and be more flexible. sometimes i feel the g on earth is too much you get that feeling?
  11. Apr 12, 2013 #10
    Not really.

    I'm not too knowledgable on the subject of meteorology, but I'm fairly certain if we had a signifigant decrease in our gravitational pull, we'd begin to lose our atmosphere at a faster rate, eventually losing it completely, and making it impossible to breath.

    So, to be honest, I'm fairly happy with the gravity we have right now.
  12. Apr 12, 2013 #11
    I thought about how we're slowing the Earth down by bringing mass from the center to the surface. But I guess we're really not digging that far into the Earth, and we're really not moving that much mass.
  13. Apr 12, 2013 #12
    I don't even think that would make a significant difference on our velocity. It shouldn't make any, as far as I know, since no outside forces are being applied to the Earth by our doing that.
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