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. artworkmonkey

    Calculate the density at the centre of the Sun

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  2. gimak

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    Hello, I'd like to work in the above named center at the University of Georgia in Athens, Georgia under Dr. Henry Schafer. However, he's a professor in the chemistry department. I'm guessing if I go in the university as a physics graduate student I can't have him as a Ph.D advisor. However, is...
  3. RandyD123

    B Big Bang Theory: If There's No Center, How Is Universe Infinite?

    The "big bang" suggests that everything came from a single point. If this is true that how can there be no center? And if everywhere is the center, then the universe by definition has to be infinite. And if the universe in infinite, then how did it become that way?
  4. M

    B Moving Center of Mass Collisions

    If I fire an electron and positron bunch both in the same direction away from my experimental accelerator rest frame such that the electron bunch is fired with higher energy towards a "read end" collision with an already fired positron bunch and they collide a short distance away from the...
  5. A

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  6. S

    Moment of inertia about a perpendicular axis through its center?

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  7. I

    I Center of inversion of cubic diamond structure?

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  8. S

    Center of mass and rotation question

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  9. E

    Finding z component of center of mass of a complex shape

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  10. K

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  11. Mr Davis 97

    Show that given conditions, element is in center of group G

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  12. G

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  13. J

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  14. N

    Find the center of a circle given a tangent line & point

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  15. S

    Rolling Down an Off Center Cylinder on an Incline

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  16. lordlarddallas

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  17. S

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  18. Mr Davis 97

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  19. Romka

    I How to determine the center of gravity of a satellite

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  20. L

    Center of Mass Balancing Question

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  21. B

    Use triple integral to find center of mass

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  22. F

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  23. Sune Irl

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  25. E

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  26. F

    How Do You Calculate Proton Beam Energy in a Lab Frame?

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  27. Ranku

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  28. K

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  29. P

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  30. jybe

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  31. F

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  32. H

    Magnetic field at the center of 3 wires carrying current?

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  33. Grinkle

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  34. Gene Naden

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  35. lfdahl

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  36. BillTre

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  37. T

    Center of mass of a disk with a hole

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  38. Spitfire

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  39. F

    Potential at the center of a sphere between two long rods

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  40. Hamza Qayyum

    I Force applied to a sphere off center of mass

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  41. karush

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  42. Roverse

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  43. Pushoam

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  44. J

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  45. Hiero

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  46. J

    Center of mass of a uniform wire

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  47. J

    Rubber Band Car- Wheel Placement and Center of Gravity?

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  48. I

    Why center of mass? Why not center of charge?

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  49. D

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  50. X

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