Couple Definition and 445 Threads

In mechanics, a couple is a system of forces with a resultant (a.k.a.net or sum) moment but no resultant force.A better term is force couple or pure moment. Its effect is to create rotation without translation, or more generally without any acceleration of the centre of mass. In rigid body mechanics, force couples are free vectors, meaning their effects on a body are independent of the point of application.
The resultant moment of a couple is called a torque. This is not to be confused with the term torque as it is used in physics, where it is merely a synonym of moment. Instead, torque is a special case of moment. Torque has special properties that moment does not have, in particular the property of being independent of reference point, as described below.

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  1. C

    Math & Physics Books for College Level: Recommendations

    So I have read both of the following books Teach yourself physics http://www.amazon.com/dp/1444103091/?tag=pfamazon01-20 complete mathematics http://www.amazon.com/dp/1444105027/?tag=pfamazon01-20 Now I am not sure where to go from here. My goal is to have a firm understanding of...
  2. D

    Can you please explain your problem in more detail?

    Homework Statement Replace the two torques acting on the structure by a single binary result. I have reduced the problem involving two force-couple system in a 3D plane to an equivalent force-couple system. Homework Equations http://img545.imageshack.us/img545/2196/problemaz.jpg Uploaded...
  3. L

    Couple Simple Grade 12 Calculas Homework Help NEEDED

    TO EVERYBODY, THIS IS NOT MY HOMEWORK. I HAVE A TEST TOM and these are some questions that I just don't know how to do, I gave attempts to some and some I am just missing something. Plus, these questions are from all over the unit so its not my homework. I need it done asap. So then I know how...
  4. C

    A couple of integration problems

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  5. H

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  6. K

    I have a couple questions for my Science gameboard. Need help

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  7. G

    Couple of questions on quantum physics from non-physicist

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  8. S

    Calculating the magnitude and sense of a couple moment

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  9. A

    Find the size of Driving couple, if given the power?

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  10. A

    Are boson fields the adjoint of the fermionic field they couple to?

    Dear Physics Forum, I read this on a wikipedia site "Technically, QCD is a gauge theory with SU(3) gauge symmetry. Quarks are introduced as spinor fields in Nf flavors, each in the fundamental representation (triplet, denoted 3) of the color gauge group, SU(3). The gluons are vector fields...
  11. L

    A couple of concepts I would like to understand.

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  12. L

    Why Do Weaker Forces Couple to More Particles?

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  13. D

    Solving MCAT Questions: Lens Adjustments and Index of Refraction Explained

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  14. 1

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  15. Z

    New to physics have a couple questions

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  16. T

    Finding the resultant couple moment

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  17. M

    Finding an Equivalent Couple for the Forces in the Figure

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  18. Z

    Help on couple of easy computer science questions?

    I got my old tests back today. And I don't understand what i did wrong?? p.s. teacher is not available at the moment( sub//part time teacher). 1. How much memory does it take to hold a 512x512 color image with 256 different levels of color(states)?? Okay, this one I just guessed and...
  19. J

    A couple of questions regarding to my calculus work.

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  20. S

    A Couple of Basic Questions about Mechanics

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  21. D

    A couple conceptual Magnetism questions

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  22. L

    A couple of questions about quantum mechanics.

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  23. J

    Couple light into photonic crystal fiber

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  24. K

    How to couple the angular momenta of a massive particle and a massless one

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  25. L

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  26. M

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  27. Ivan Seeking

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  28. V

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  29. H

    How to couple apin angular momenta of four electrons?

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  30. S

    3d dynamics- determine the couple exerted

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  31. C

    A couple basic physics questions(vector sum and kinematics)

    Homework Statement I already know the answers because this is a review sheet, but I don't understand how to solve number 1, and I don't understand the wording of number 2. 1) A particle is moving along the x-axis and has a position given by x=(24t-2.0t3)m, where t is in seconds. How far is...
  32. B

    Am struggling with these couple of questions

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  33. E

    Perturbation theory - need a couple of articles

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  34. N

    White deer couple producing viable offspring through several generations?

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  35. A

    How do electrons couple to gauge field?

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  36. D

    Just a couple of questions on how to type out problems.

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  37. J

    Life of married couple in your culture ?

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  38. A

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  39. U

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    I really need someone to tell me I'm wrong and why here or this is going to keep bothering me. As far as I'm aware, a thermocouple works by heating the same side of two different materials, one p-type and one n-type. Since charge carriers also serve to conduct thermal energy, the charge...
  40. D

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  41. G

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  42. marcus

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  43. Z

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  44. O

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  45. A

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  46. S

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  47. C

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  48. E

    Schools A Couple Graduate School Application Questions

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  49. W

    Replacing column by equivalent force and couple

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  50. W

    How to set up differential equations for algebraic manipulation?

    Hey guys, We skimmed a chapter on differential eqns in my semester 2 calculus class and we have a worksheet to fill out. I'm having trouble setting up the last 3 problems in this sheet. http://dl.dropbox.com/u/85600/DIFF_HW.PDF" I'm pretty sure It's all just algebraic manipulation to...
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