Center Definition and 1000 Threads

In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force may be applied to cause a linear acceleration without an angular acceleration. Calculations in mechanics are often simplified when formulated with respect to the center of mass. It is a hypothetical point where the entire mass of an object may be assumed to be concentrated to visualise its motion. In other words, the center of mass is the particle equivalent of a given object for application of Newton's laws of motion.
In the case of a single rigid body, the center of mass is fixed in relation to the body, and if the body has uniform density, it will be located at the centroid. The center of mass may be located outside the physical body, as is sometimes the case for hollow or open-shaped objects, such as a horseshoe. In the case of a distribution of separate bodies, such as the planets of the Solar System, the center of mass may not correspond to the position of any individual member of the system.
The center of mass is a useful reference point for calculations in mechanics that involve masses distributed in space, such as the linear and angular momentum of planetary bodies and rigid body dynamics. In orbital mechanics, the equations of motion of planets are formulated as point masses located at the centers of mass. The center of mass frame is an inertial frame in which the center of mass of a system is at rest with respect to the origin of the coordinate system.

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  1. N

    Center of Gravity and Center of Pressure

    Hello, everyone. This is my first post! Center of gravity does not seem like a difficult concept to grasp, but for some reason, I find it difficult to put into words. Would I be correct in saying: the center of gravity is a point on an object that represents the average position of an object's...
  2. S

    Center of percussion - baseball bat theorem

    look figure (b) suppose that baseball deliver F through horizontal motion. imagine that the O point of the system is same line of F (+x is F direction) then before percussion, the angular momentum of the system is "0" because r and v of baseball are same direction (L = r x mv = 0) so after...
  3. S

    Design -- horizontal I-beam with center loading....

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  4. T

    I Center of the Universe: What Again

    I've recently read that the universe is now estimated to be about 95 billion light years in diameter. This was based on what we now can observe (Hubble Deep Field for example), what is estimated to be seen with new technology (James Webb) and an estimate of what's beyond that which we can't yet...
  5. C

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  6. Daleri Mc Rileda

    B How Far Is It To The Center Of The Milky Way/Tootsie Pop?

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  7. N

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  8. R

    Finding Mass Center of a Circular Disc with Hole & Weight

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  9. T

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  10. B

    B Does time stop at the center of a black hole?

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  11. E

    Center of gravity change and acceleration

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  12. S

    B Using center of mass for loop de loop

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  13. T

    B Rod falling radially towards the center of a mass

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  14. Zarich12

    B How to find the center of gravity of an object

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  15. ing_it

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  16. G

    B What kind of force acts in the center of the Earth?

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  17. RJLiberator

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  18. S

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  19. Allen_Wolf

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  20. Josephthe2

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  21. P

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  22. Monoxdifly

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  23. X

    B Gravitation with multiple objects by using center of mass

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  24. Elvis 123456789

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  25. Alltimegreat1

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  26. Elvis 123456789

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  27. F

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  28. F

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  29. F

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  30. A

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  31. U

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  32. W

    Center of gravity vs center of buoyancy

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  33. P

    Is the center of mass truly where all forces act in a system?

    As far as I know in a system of particles or a body there is a point that behaves like all the forces on the system are applied at this point, but are these forces really applied in this point? Can you explain please, I thought at this and I arrived at the conclusion that these forces aren't...
  34. T

    B The Center of the Earth and Black holes and Gravity

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  35. S

    MATLAB Center Wavelength of Fiber Bragg Grating Filter

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  36. H

    Automotive How do Center differentials work

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  37. 4

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  38. evinda

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  39. S

    Can a Center Tapped LC Circuit Reduce Potential Difference Across the Inductor?

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  40. evinda

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  41. websterling

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  42. CrackerMcGinger

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  43. SDewan

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  44. gracy

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  45. CrazyNinja

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  46. L

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  47. G

    Transforming Equations: How to Solve for 3-22a | Center of Pressure Homework

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  48. T

    MHB Starting with center of thrust to find amount of force on each point?

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  49. E

    Integrals to Solve Area and Center of Mass of a Cut Circle

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  50. A

    B How to calculate center of mass & centerline a of a boat?

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