Modes Definition and 281 Threads

A normal mode of an oscillating system is a pattern of motion in which all parts of the system move sinusoidally with the same frequency and with a fixed phase relation. The free motion described by the normal modes takes place at fixed frequencies. These fixed frequencies of the normal modes of a system are known as its natural frequencies or resonant frequencies. A physical object, such as a building, bridge, or molecule, has a set of normal modes and their natural frequencies that depend on its structure, materials and boundary conditions. In music, normal modes of vibrating instruments (strings, air pipes, drums, etc.) are called "harmonics" or "overtones".
The most general motion of a system is a superposition of its normal modes. The modes are normal in the sense that they can move independently, that is to say that an excitation of one mode will never cause motion of a different mode. In mathematical terms, normal modes are orthogonal to each other.

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  1. J

    Questions about radiative decay modes

    Let's take for example the decay K+ -> pi+,pi0,gamma This can proceed via direct emission or inner bremsstrahlung. I have questions for each of these modes 1. For inner bremsstrahlung, it is a final charged product that radiates, correct? In this case the pi+. What is causing the...
  2. M

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  3. P

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  4. L

    Springs, Normal Modes, and Center of Mass coordinates

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  5. R

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  6. T

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  7. I

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  8. A

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  9. H

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  10. J

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  11. B

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  12. B

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  13. B

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  14. D

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  15. P

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  16. O

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  17. J

    When to Use TE, TM, & TEM Modes for Modeling Optical Fields

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  18. W

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  19. D

    Normal Mode ODEs: Uncovering the Mysteries

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  20. R

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  21. G

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  22. T

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  23. A

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  24. C

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  25. Astronuc

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  26. P

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  27. quasar987

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  28. F

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  29. J

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  30. R

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  31. Clausius2

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