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Best physics problem ever

  1. Nov 7, 2009 #1
    Dear Sir,

    I am a high school student and have a problem.

    My teacher and I were talking about Satan. Of course you know that when he fell from heaven, he fell for nine days, and nine nights, at 32 feet a second and was increasing his speed every second.

    I was told there was a foluma [formula] to it. I know you don't have time for such little things, but if possible please send me the foluma.

    Thank you, Jerry

    Quite possibly a letter sent to Einstein by a child, I was told.
  2. jcsd
  3. Nov 7, 2009 #2


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    The formula is simple; there's no such thing as Satan. :rolleyes:
  4. Nov 7, 2009 #3
    Some theorists believe LHC will spawn him :devil: Watch and laugh:

    Last edited by a moderator: Sep 25, 2014
  5. Nov 7, 2009 #4


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    That assumes that the acceleration due to gravity between Heaven and Hell is constant and equal to that of the Earth.
  6. Nov 7, 2009 #5
    Then we could calculate the distance between heaven and hell.

    It seems surprisingly small.

    Maybe this is actually a telling metaphor?
  7. Nov 7, 2009 #6


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    Just for fun though...

    At what altitude is Heaven, by this logic.

    9 days' fall to Earth, accounting for gravitational gradient, would give us what altitude?
  8. Nov 7, 2009 #7
    There is a small problem. We are told that he falls at 32 feet per second, a constant velocity, and then told that he increases his speed every second (by an unknown amount, unless he is falling to Earth or another known mass). This is contradictory, unless the problem statement is that he is accelerating at 32 feet per second every second, which is approximately the acceleration due to gravity near sea level. Unfortunately, a 9 day fall cannot be anywhere near sea level, unless he is falling through a hole cut in the Earth.
    Last edited: Nov 7, 2009
  9. Nov 7, 2009 #8
    Is there atmosphere present at the time of Satan's fall? If so, we must account for air friction; as he enters the atmosphere near the end of his fall he will brake to terminal velocity in air, which depends on his cross-section and mass.
    Assuming no friction and that he is actually falling to Earth's sea level, where Earth has mass M, we can use energy methods:
    [tex]9 \text{ days} = \int_\text{sea level}^x \frac{\pm dx}{\sqrt\frac{2GM}{x}}[/tex]
    Solving for the displacement x gives us:
    [tex]x = \left(\pm 3\sqrt\frac{GM}{2}(9 \text{ days}) + (\text{sea level})^\frac{3}{2}\right)^\frac{2}{3}[/tex]
    where the numerical value of G must be adjusted for days instead of seconds.
    The Earth page on Wikipedia gives average values for sea level and mass and assuming exact 24-hour days, we have approximately 6434 km, which is pretty close to the radius of the Earth.
    Last edited: Nov 7, 2009
  10. Nov 7, 2009 #9


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    Yeah, got to agree with Danger. The problem is non-existent.
  11. Nov 7, 2009 #10
    Henceforth, this shall be know as "Satan's law".
  12. Nov 7, 2009 #11
    I once saw it calculated that heaven is hotter than hell - but that might violate the guidelines (no kidding).
  13. Nov 7, 2009 #12


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    Was that this?

  14. Nov 7, 2009 #13


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    I believe I saw this same mathematics prove that Women = Evil.
  15. Nov 7, 2009 #14
    Well, women take time and money, so [itex]\mbox{Women} = \mbox{Time}\cdot\mbox{Money}[/itex].

    I have often heard it claimed that time is money, [itex]\mbox{Time} = \mbox{Money}[/itex], so we have [itex]\mbox{Women} = \mbox{Money}^2[/itex].

    But since money is the root of evil, [itex]\mbox{Money} = \sqrt{\mbox{Evil}}[/itex], we know that [itex]\mbox{Women} = \left(\sqrt{\mbox{Evil}}\right)^2 = \mbox{Evil}[/itex].
  16. Nov 7, 2009 #15


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    Fall speed from heaven = 2 * X;

    Where X is a constant for adjusting the fall speed to your liking.
  17. Nov 7, 2009 #16


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  18. Nov 7, 2009 #17
    I think I saw the calculation in an old Ripley's Believe it or Not. There were references from a religious text, saying how high heaven is and where hell is located. Then using some earth physics - voila!

    I wonder if the student you quote ended up in engineering, divinity or their unification: theoretical physics.
  19. Nov 8, 2009 #18
  20. Nov 8, 2009 #19
    Would be funny if you still have the proof somewhere and you can post it as a joke.
  21. Nov 8, 2009 #20


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    Dearly Missed

    This then yields the equation:
    Thus, the problem is that it is evil to love the fact that you love women.
    Straight men should regret the fact that they are not gay, while lesbians ought to regret they are not straight, I suppose :smile:
    Last edited: Nov 8, 2009
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