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Perpendicular Everything

  1. Jul 10, 2003 #1
    Straight Aristocracy

    If the latter part of this is true it postulates that if an object which was put into motion by an unknown entity in zero gravity is moving in a circle a force must be acting upon it. Hence, no object will inertially move in a circle unless it is a spin (rotation on its' axis). And therefore, all movement in this universe (straight, circular, diagonal; everything) is just a configuration of perpendicular forces with differing magnitudes acting on differing points on a body.

    Experimentally it seems as if this is backed up. If you take a string, a iron square with a hole in the center, tie the string to the hole and then spin the string its' circular movement is actually the iron mass attempting to find a why out so it can move in a straight line (e.g when you let go it moves straight. It doesn't continue the circle till its' energy runs out). I have a question that concerns how much energy would be lost by balls (spheres) moving in a circular pipe. Let me use these examples to help clarify:

    (1) If you take two balls, launch them at the same speed, with one going to a 3 meter long straight pipe (hollow cylinder) and the other in a 3 meter long circular pipe (notice same length) which one would win and why or would it be a tie?

    Wouldn't the the ball going through the circle lose more energy due to the balls constant attempt to break the circle?

    (2) Now let's say a vehicle with a curb weight of 3000LB is moving at 80MPH and the driver suddenly turns the wheels as far as possible. The car will skid because it wants to continue its perpendicular habit. But if your going the same speed and turn the wheels only slightly it will not skid because the circle isn't as circular and hence, it takes less energy to turn correct?

    (3) Finally, consider a spiral of a hollow cylinder in which from the initial start the subsequent circles continue to shrink as they go down. If you throw a ball through it will the ball slow down as it gets closer to the center as the circles continue to shrink?

    If it does take more energy to move a ball through a smaller circle is the energy lose considerable? Or is it small enough to be ignored? Maybe I have a completely wrong idea? I was just wondering about this circular phenomenon so if you have an answer please reply!
    Last edited: Jul 13, 2003
  2. jcsd
  3. Jul 10, 2003 #2


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    This whole thread seems to be based on an incorrect word: "perpendicular" The word "straight" in the quote is correct, the word "perpendicular" is not.

    Yes, for one thing there will be friction as it constantly presses against the pipe constraining it. IF you assume no friction, perfectly elastic collisions, there would be no energy loss.

    "isn't as circular"? You mean a longer radius- one circle is not "less circular" than another!
    It takes more FORCE to make the sharper turn- force is not energy.

    With friction as the ball hits the walls, yes, without friction, no- assuming that the circles remain large enough for the ball to actually go through.

    In any case, an object moving in a circle at constant speed keeps constant kinetic and potential energy: it does not require any energy to keep it going (neglecting friction of course). The size of the circle is irrelevant.
  4. Jul 10, 2003 #3
    I remember something called d'Alembert's law or so, which states that stationary obstacles don't do any work, i.e. don't change the energy of the system. It applies to the 'no friction' case, only.
  5. Jul 13, 2003 #4
    To HallsofIvy:

    Oh yeah your right. Perpendicular is the way electromagnetic waves makeup travel; electric and magnetic fields at right angles to each other. For some reason I thought it was a scientific definition of straight motion, but now that I looked it up in the dictionary I see that is incorrect. So let me rename it "Straight Aristocracy" to refer to straight motions dominance in movement.

    Anyway, let me get a few things straight. Firstly, your saying only due to friction would the balls lose energy.

    Secondly, that the size of the circle (radius; line from center to circumference) does not make the circle anymore circular than larger or smaller circles. In other words, as a general rule no circle is better than another?

    Thirdly, still is it true that all movement is just different configurations of forces influences bodies in a straight way?

    And lastly;
    Assume magnetic forces are keeping the balls from touching the interior of the pipes. And also that the pipes are a vacuum theoretically possessing no gas. In this case, the configuration of the pipes (if straight or circle) wouldn't be of any hindrance to the balls advancement in the pipe?
    Last edited: Jul 13, 2003
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