What is Center of mass: Definition and 915 Discussions

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. V

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    Homework Statement A dog with mass 11 kg stands still in a boat with mass 45 kg. the dog is 20 meters from the shore. It then walks 8 meters in the boat towards the shore. how far is the dog from the hore aftter this? Homework Equations center of mass equation The Attempt at a...
  2. P

    Where Is the Center of Mass in a Right Triangle?

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  3. I

    Center of mass: mass's on a right triangle system

    A system consists of three particles located at the corners of a right triangle as shown below. Mass 1 is 7.0 kg, mass 2 is 6.4 kg, and mass 3 is 9.9 kg. If the distances a equals 15.8 m and b equals 2.0 m, then what is the center of mass (in m) in the vertical direction? Y center of...
  4. I

    Center of mass: 2 objects in triangle system

    Three objects of different masses are located at the corners of the triangle shown in the picture. If distance a equals 4.21 m, b equals 1.55 m, and c equals 11.93 m, then what is the center of the mass (in m) of the system in the horizontal with respect to the origin? X center of...
  5. X

    Finding the Center of Mass of a Meter Stick with Variable Mass Density

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  6. E

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  7. E

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  8. B

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  9. V

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  10. C

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  11. I

    Center of mass of a uniform density square centered at the origin. Offset by width/4?

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  12. H

    Calculate the moments Mx, My and the center of mass

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  13. J

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  14. G

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  15. G

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  16. H

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  17. J

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  18. F

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  19. U

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  20. T

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  21. A

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  22. M

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  23. M

    Simple Center of Mass Question

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  24. 2

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  25. M

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  26. N

    Rotation about the Center of Mass

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  27. M

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  28. C

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  29. M

    Center of mass equation for an ellipsoid?

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  30. e2m2a

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  31. S

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  32. S

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  33. M

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  34. J

    Increase of velocity of center of mass of a certain system

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  35. M

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  36. R

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  37. F

    General question about center of mass

    I hope this is the right section. consider the CM of a uniform ring. Suspend that ring by light cables above the earth, by a crane maybe? Where is the rings center of mass now? If this system was in space (crane, cables, ring), the CM would be somewhere else right? If the ring was...
  38. C

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  39. P

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  40. M

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  41. S

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  42. S

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  43. O

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  44. C

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  45. H

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  46. P

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  47. O

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  48. Y

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  49. E

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