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

    An ornament for a courtyard at a World's Fair is to be made up of four large metal spheres

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  2. Greg Bernhardt

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  3. S

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  4. ActaPhysica

    I Return to the center of the Earth

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  5. J

    I Rotational stability and Fosbury Flop questions

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  6. L

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  7. P

    I Rolling Motion direction of Velocity center of mass

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  8. S

    Opening a portal to the center of the Sun

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  9. H

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  10. V

    Force between point charges at the center of two spherical shells

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  11. V

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  12. Lotto

    B Can we say that a charged balloon has a center of charge?

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  13. shivajikobardan

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  14. greg_rack

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  15. paulimerci

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  16. A

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  17. kyphysics

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  18. sachin

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  19. C

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  20. C

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  21. Ahmed1029

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  22. N

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  23. qnt200

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  24. V

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  25. S

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  26. J

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  27. V

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  28. A

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  29. P

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  30. A

    Find the inertia of a sphere radius R with rotating axis through the center

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  31. A

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  32. K

    Analyzing applied torque to one of lug nuts instead of wheel center

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  33. L

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  34. tivva

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  35. I

    B Calculate needed dimensions of table - Center of mass, levers etc

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  36. L

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  37. A

    I If the center of gravity changes on a die, how do the odds change?

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  38. A

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  39. T

    B T: "Exploring the Possibility of a Theoretical Center in a Finite Universe

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  40. N

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  41. S

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  42. ektov_konstantin

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  43. lela

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  44. guyvsdcsniper

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  45. R

    B Is it the nucleus or a proton at the center?

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  46. F

    A Center of a linear algebraic group

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  47. Dan Rozenfarb

    B Please help in explaining 'we are not the center of the Universe'

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  48. Istiak

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  49. karush

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  50. D

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