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So Is It Angular Or Linear?

  1. Apr 1, 2004 #1
    Is there any restriction to what type of acceleration should give Newton’s force - mass ratio? Should it be angular or linear or electric or whatever acceleration? The fact that the rigid bar on which the weights hold IS rigid means that the weights are rotating around the center of the lever and the angle of rotation for each weight is same. So, this force - mass ratio either could or must be expressed thru this angle, which enables that ratio to be equivalent with the angle. This also enables that ratio to be equivalent with the angular acceleration. Angular acceleration is not same with the linear one. If it was then it could be same also with electric acceleration that I define like some Coulombs over seconds squared.

    So what type of acceleration gives Newton’s force - mass ratio?

    After all I don’t think even angular acceleration is necessary to simulate the motion in one system. Look:
    D_1 = (random, random, random) - nonzero distance of first weight.
    F_1 = (random, random, random) - nonzero force of first weight.
    D_2, F_2 - distance, force of second weight.
    n = random (1, 100) - ratio of the distances.
    A = random (0, 359) - the angle of rotation same for all.
    [tex]make D_2 = \frac {-n}{|D_1|} D_1 [/tex]
    [tex]make F_2 = \frac {-|D_1|}{|D_2|} F_1 [/tex]
    [tex]for i = 1 and 2 make [/tex]
    [tex]new (F_i) = cos(a) F_i - \frac {|F_i | sin(a)}{|D_i |} D_i [/tex]
    [tex]new (D_i) = cos(a) D_i + \frac {|D_i | sin(a)}{|F_i |} F_i [/tex]
  2. jcsd
  3. Apr 1, 2004 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Newton's 2nd Law can be expressed for translational acceleration or angular acceleration (for rotational motion). For translational motion: a = F/m; for rotational motion: α = Torque/I.
    Acceleration is a kinematic concept: there is no "electric" or other kind of acceleration.
  4. Apr 1, 2004 #3
    But there is a big difference between angular and linear:
    -angular expresses in deg/sec^2
    -linear in m/sec^2
    What will decide which one I should use for Newton's froce - mass ratio?
  5. Apr 1, 2004 #4
    Angular acceleration is expressed in radians/sec^2.

    (Stupid equation here was deleted)

    For a circle with a radius of 1 meter:
    one radian is equivalent to 1 meter of arc length.

    You see?
    Last edited by a moderator: Apr 1, 2004
  6. Apr 1, 2004 #5
    Ok, then I'll walk 500 radians to return home.
    No man Pi radians is only equivalent (not equal) to 180 degrees.
  7. Apr 1, 2004 #6
    Sorry, a bit cranky today are we?

    Edited previous post.

    Dimensional analysis. You see?

    P.S. I'd say that walking any more than pi radians(or in this case 3.14... meters) to return home would be wasteful. I think I could do it in 2 radii(2 meters).
    Last edited by a moderator: Apr 1, 2004
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