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Science questions not worth a thread I: I'm a moron!

Discussion in 'Science & Technology' started by The Imp, May 4, 2010.

  1. nc-1701

    nc-1701 bombombedum

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    Surface area of a sphere is 4*Pi*r^2, radius of the moon is 1737.1 km. So the surface area is about 37900006.1096 km^2.

    Surfacearea of Earth with radius of 6371 km would have an area of 509805890.96 km^2.

    Divide them and we get that the moon would cover about 7.4% of the Earth's area.


    Math ftw
     
  2. Cutlass

    Cutlass The Man Who Wasn't There.

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    You didn't say surface area. The volume of it is much greater.
     
  3. Bluemofia

    Bluemofia F=ma

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    Also similar to the "what is the length of the coastline of Britain" problem.

    Depends on your precision of measurement.
     
  4. Perfection

    Perfection The Great Head.

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    Why the hell not just look up the surface area stats instead of approximating them? :confused:

    Math FTL.


    Also, if for some reasons it was easier to look up radius, then you'd just calculate

    rmoon^2/rearth^2

    smart math FTW


    :smug: :smug: :smug:
     
  5. Xanikk999

    Xanikk999 History junkie

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    What is the finest substance known (Either man made or natural)?
     
  6. uppi

    uppi Deity

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    What do you mean with "finest"? The purest?
     
  7. madviking

    madviking north american scum

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    I think he means by grain.
     
  8. ParadigmShifter

    ParadigmShifter Random Nonsense Generator

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    It's made easier by the fact it is 4x the damage of a single D4* (let's call it D4*).

    I think the average damage for a D4* will be

    2.5 + 0.25 * 2.5 + 0.25^2 * 2.5 ...

    = sum( n = 0 to inf ) 2.5 * 0.25^n

    = 3 1/3

    (from Wolfram Alpha http://www.wolframalpha.com/input/?i=sum(+n+=+0+to+inf+)+2.5+*+0.25^n )

    so it would be 3.333.. * 4 = 13.333...
     
  9. ParadigmShifter

    ParadigmShifter Random Nonsense Generator

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  10. ParadigmShifter

    ParadigmShifter Random Nonsense Generator

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    Sometimes you can do infinite summations. It's often hard to find a closed form solution, for example

    1 - 1/3 + 1/5 - 1/7 + 1/9 - ... = pi/4

    which needs trigonometry and integration to prove.
     
  11. ParadigmShifter

    ParadigmShifter Random Nonsense Generator

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    The series only converges to a/(1-r) if r < 1.

    EDIT: Actually, if |r| < 1 i.e.

    -1 < r < 1

    EDIT2: Fascinating subject convergent series anyway.
     
  12. sanabas

    sanabas Psycho Bunny Hall of Fame Staff

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    Yep. Also, occasionally having a brain like a sieve can be fun. Last time I tried to remember the formula for sum of a geometric progression, I couldn't, so got to sit down & derive it & prove it myself. Was fun.
     
  13. tycoonist

    tycoonist Deity

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    I like to prove the mathematical formulas i used in the half hour i always have left in my maths exams :D
     
  14. Xanikk999

    Xanikk999 History junkie

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    Yes this is what I mean anyone know?
     
  15. Eran of Arcadia

    Eran of Arcadia Stormin' Mormon Retired Moderator

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  16. IdiotsOpposite

    IdiotsOpposite Boom, headshot.

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    What is the geometric significance of a line integral over a vector field?
     
  17. SS-18 ICBM

    SS-18 ICBM Oscillator

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    Don't think there would be too many intermolecular forces at work, so it might be the case. I don't know about possible quantum effects though.
     
  18. uppi

    uppi Deity

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    No, Hydrogen usually builds a H2 molecule, so a crystal built from Hydrogen is usually diatomic. Helium is the atom that is hardest to get to bound with other atoms.

    The original question is hard to answer without some boundary conditions. The answer very much depends on how exactly you define grain and what states of matter you allow.

    One can make the case, that there are states of matter, that have atoms, protons, electrons or even photons as the particles that make up grain. So one could argue, that the smallest grain is exactly zero (and it gets quite muddy here, as we do not know whether some particles have a "size" larger than zero).

    But thinking of photons as grains is quite strange and probably not the intention, so a stringent definition of grain is needed (and keep in mind, that one can make pretty exotic states of matter that defy the common classifications). If you have such a definition, pick the smallest particle that fits it and you have the answer.
     
  19. tycoonist

    tycoonist Deity

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    I can't see why it would be monatomic, looking at the question from a chemistry point of view. I guess there could be quantum effects on that scale.
     
  20. Narz

    Narz keeping it real

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    Another question about the aging process.

    If aging is mostly caused by improper cell division &/or mutations (probably a gross oversimplification, feel free to amend/correct) then how does anti-aging occur? Do the cells actually repair themselves?

    I ask because I don't want to get old! I'm having a lot of issues with stress & undersleeping & I know I'm causing my body some damage & want to make up for it.
     

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