Lydbølger- stående bølger for strengeinstrumenter

Lyd er ligesom lys. Det går nemlig rundt om hjørner. Det kan være interessant.

         for en streng er der knude i hver ende af strengen

              og for grundtonens bølgelængde λ
              gælder

                                            λ   
                                     L = ---
                                            2

                                   
                                      1       1
                                     ---  =  -
                                     2L      λ

                                            v       v
                                      f =  -  =   --
                                            λ       2L

       1. overtone
                                              v
                                      f₁ =  --
                                               L

       2. overtone
                                             2v
                                      f₂ =  --
                                              L
        ..........

       n. overtone
                                             2^n-1 • v
                                      f_n =  --------
                                                   L

korrektion af #2

         for en streng er der knude i hver ende af strengen

              og for grundtonens bølgelængde λ
              gælder

                                                 λ   
                                     L = 1• ---
                                                 2

                                            v
                                     f =  ---
                                           2L

       1. overtone
                                                   v
                                      f₁ = 2 • ---
                                                  2L

       2. overtone
                                                   v
                                      f₂ = 3 • ---
                                                  2L
        ..........

       n. overtone
                                                           v
                                      f_n =  (n+1) • ---
                                                          2 L

    strengens udgående tværbølger interfererer med dens reflekterede tværbølger, hvorved der dannes
    "stående" steder med knuder og buge