What is Central forces: Definition and 29 Discussions

In classical mechanics, a central force on an object is a force that is directed towards or away from a point called center of force.







F




=

F

(

r

)
=

|

F
(

r

)

|





r

^





{\displaystyle {\vec {F}}=\mathbf {F} (\mathbf {r} )=\left\vert F(\mathbf {r} )\right\vert {\hat {\mathbf {r} }}}
where







F







{\displaystyle \scriptstyle {\vec {\text{ F }}}}
is the force, F is a vector valued force function, F is a scalar valued force function, r is the position vector, ||r|| is its length, and








r

^






{\displaystyle \scriptstyle {\hat {\mathbf {r} }}}
= r/||r|| is the corresponding unit vector.
Not all central force fields are conservative or spherically symmetric. However, a central force is conservative if and only if it is spherically symmetric or rotationally invariant.

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  1. deuteron

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  2. D

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  3. Saptarshi Sarkar

    Conservation of angular momentum under central forces

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  4. K

    Closest approach from initial velocity and impact parameter

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  5. sams

    A How to calculate Saturn's mass from Kepler's third law?

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  6. sams

    Why are central force fields irrotational and conservative?

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  7. Abhishek11235

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  8. O

    Angular momentum conserved for central forces not at origin?

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  9. Satvik Pandey

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  10. T

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  11. saadhusayn

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  12. P

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  13. A

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  14. R

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  15. P

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  16. P

    Planar motion in central forces.

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  17. U

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  18. O

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  19. A

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  20. W

    Simple harmonic motion and central forces.

    Homework Statement Assuming Earth to be a solid sphere, show that if a straight hole were drilled from pole to pole that a particel dropped would undergo simple harmonic motion. Show that the period of the oscillation depends only on the Earth's density and is independent of size. What is...
  21. A

    Central forces in elliptic and parabolic orbits

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  22. K

    String through hole - central forces

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  23. P

    Radial Equation for Two-Body Central Forces

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  24. R

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  25. T

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  26. I

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  27. C

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  28. B

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  29. F

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