Moment Definition and 1000 Threads

In mathematics, the moments of a function are quantitative measures related to the shape of the function's graph. If the function represents mass, then the first moment is the center of the mass, and the second moment is the rotational inertia. If the function is a probability distribution, then the first moment is the expected value, the second central moment is the variance, the third standardized moment is the skewness, and the fourth standardized moment is the kurtosis. The mathematical concept is closely related to the concept of moment in physics.
For a distribution of mass or probability on a bounded interval, the collection of all the moments (of all orders, from 0 to ∞) uniquely determines the distribution (Hausdorff moment problem). The same is not true on unbounded intervals (Hamburger moment problem).
In the mid-nineteenth century, Pafnuty Chebyshev became the first person to think systematically in terms of the moments of random variables.

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  2. M

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  3. MrGenetic

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  4. M

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  5. C

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  6. B

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  7. G

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  8. Z

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  9. A

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  10. Z

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  11. N

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  12. Jefffff

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  13. F

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  14. N

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  15. H

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  16. C

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  17. yavorh

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  18. lichenguy

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  19. T

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  20. S

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  21. T

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  22. L

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  23. D

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  31. A

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  33. J

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  34. D

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  35. F

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  36. A

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    Ok, so this is an undergraduate level question probably but consider this R. C. Hibbeler's Textbook on Mechanics of Materials says this about thrust bearings and smooth journal Bearings : In other words, it says nothing about reaction moments. Now this chart has other 2D connection types...
  37. J

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  38. S

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  39. J

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  40. B

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  41. S

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  42. C

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  43. G

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  44. G

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  45. J

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  46. marsupial

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  47. S

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  48. S

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  49. A

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  50. Z

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