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I'm questioning the validity of gravity and Coulomb's law?

  1. Aug 8, 2004 #1
    The law of lever rules without exceptions!

    "The ratio of the lifting weight and the weight lifted is inverse the ratio of their distances to the center" - Aristotle's followers.

    "Magnitudes are in equilibrium on distances reciprocally proportional to their weights" - Archimedes.

    See any exceptions in these statements?

    Where is the rigid bar in these two statements?

    www.geocities.com/dedanoe
     
  2. jcsd
  3. Aug 8, 2004 #2
    The law of gravity according to Newton is:

    [tex]F=G\frac{M_1M_2}{R^2}[/tex]

    The Coulomb's law is formally same:

    [tex]F=-k\frac{Q_1Q_2}{R^2}[/tex]

    The gravity law that respects the law of lever must look like this:

    [tex]\frac{F_1}{D_2}=\frac{F_2}{D_1}=G\sqrt{\frac{M_1M_2}{D_1D_2}}[/tex]

    The Coulomb's law that respects the law of lever must look like this:

    [tex]\frac{F_1}{D_2}=\frac{F_2}{D_1}=k\sqrt{\frac{Q_1Q_2}{D_1D_2}}[/tex]

    Until we resolve this we cannot recall these laws in their previous forms!
    www.geocities.com/dedanoe
     
  4. Aug 8, 2004 #3
    I forgot to subscribe...
     
  5. Aug 8, 2004 #4
    by the way the law of lever has this form:

    [tex]\frac{F_1}{F_2}=\frac{M_1}{M_2}=\frac{Q_1}{Q_2}=\frac{D_2}{D_1}[/tex]
     
  6. Aug 8, 2004 #5

    Chronos

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    Once I dated this girl I thought was a bit heavy. I tested my hypothesis on a teeter-totter. I measured the lever distance difference using a Stanley tape measure [which is NBS traceable]. By lever formula calculations, she was at least 3 standard deviations heavier than I. I tried to lift my own weight off the ground, and could, I tried to lift her off the ground and could not. I therefore conclude the lever formula is correct [on the light side] within two standard deviations.
     
  7. Aug 8, 2004 #6
    the Earth / Moon is not a "lever system" so i'm not sure where you're getting that idea.

    "where is the rigid bar?"
     
  8. Aug 8, 2004 #7

    Chronos

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    My bad, did not read link. Wrong formula. The lever formula only works in 2 dimensional space.
     
  9. Aug 8, 2004 #8
    Is the law of lever something we should have learned in school ( I missed it if so ) or is it a contribution of your own? :smile:

    Keep on chuggin !!

    Vern
     
  10. Aug 8, 2004 #9

    Doc Al

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    The way to resolve it is for you to realize that the "law of the lever" is very limited and only applies to real levers with forces perpendicular to the rigid bar. It has nothing to say about Newton's law of gravity or Coulomb's law.
     
  11. Aug 8, 2004 #10
    more importantly if the lever only applies force directly to "the bottom" of the object then inertia dictates that they spiral outwards away from each other.

    2. it doesn't explain why they would be rotating around each other in the first place.

    3. if you assume the two objects ARE connected rigid to a hypothetical "bar" then there is measurable centripetal force which would cause all the water on the planet to fly off it

    i don't think it holds together, but maybe you have a few arguments in context that i have overlooked...
     
  12. Aug 9, 2004 #11
    The law of lever needs no rigid bar.
    Where in the Archimedes' statement do you see rigid bar?
    The force always points in direction of displacement!

    Assume the earth has:
    F:=(10,0,0);D=(0,1,0)

    The moon would have:
    F:=(-5,0,0);D=(0,-2,0)

    Now, for each apply:
    NewF=Fcos(alpha)-aDsin(alpha)
    NewD=Fsin(alpha)+aDcos(alpha)

    It's only another form of the law of lever where NewF*NewD=F*D is equivalent with NewF= aD and F= a*NewD

    www.geocities.com/dedaNoe
     
  13. Aug 9, 2004 #12
    Archimedes says:
    "Magnitudes are in equilibrium on distances reciprocally proportional to their weights".

    Where in this law do you see a rigid bar or necessity of it?

    Vern:
    The law of lever is not mentioned in school because if so Newton would've fall down earlier.
     
  14. Aug 9, 2004 #13

    arildno

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    This nonsense from your own website says it all:
    "The energy and the lever
    According to the widely accepted physics, the vector product of the force and the distance of one weight is rotational momentum. I disagree with that because I am sure that this kind of product is already defined in physics as energy. This way Newton times meters give nothing but Jules - counter parts for energy."
     
  15. Aug 9, 2004 #14
    Yes it says extreme force - extreme energy; extreme energy potential - extreme distance but...
    Whatever that part of my page says it's not in the context of this topic, right?

    Newton's gravity and Coulomb's law don't respect the law of lever!
    Prove that wrong or right if you want to contribute in this discussion?
     
  16. Aug 9, 2004 #15
    Magnitudes are in equilibrium on distances reciprocally proportional to their weights - The law of lever according to Archimedes.

    Where in this statement do you see any rigid bar?
     
  17. Aug 9, 2004 #16

    Doc Al

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    "law of the lever" applies to levers... duh

    Perhaps Archimedes just assumed that by calling this "the law of the lever" that you would realize that it applied to levers.

    You do know what a lever is, don't you?
     
  18. Aug 9, 2004 #17

    Doc Al

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    do you know what a lever is?

    Do you know what a lever is?
     
  19. Aug 10, 2004 #18
    All is nothing but highly complex lever in equilibrium.
     
  20. Aug 10, 2004 #19
    I do know what lever is and my idea of "lever" happens to be the widest and most general one. I think that all is nothing but highly complex lever in equilibrium. Even the earth and the moon make a lever although there is no rigid bar there to support them. The center of that invisible lever is the center of mass in the system. With respect to the center every one in the system has its own central distance. Their forces are same by direction as their displacements. The law of lever covers the interaction between the earth and the moon.
     
  21. Aug 10, 2004 #20

    Doc Al

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    Nonsense. No rigid bar (or equivalent) = no lever. It's as simple as that. The "law of the lever" applies to real levers only. Real ones, not invisible, imaginary ones.
     
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