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O





                                                                                 O


                                     a                b                  c
                                                 Figure 6.14


                   .   In common  case, when rotation takes  place around  the arbitrarily
                  axes of XYZ (fig. 4.17) relationship between the components of moment
                  of inertia  becomes  another aspect


                                       L X   I    X   I       I    Z
                                                XX
                                                           XY
                                                                Y
                                                                      XZ
                                       
                                             L   I  X   I     I    X  ,                         (6.39)
                                                YX
                                                          YY
                                                              Y
                                                                    YZ
                                        Y
                                       
                                         L
                                                               Y
                                                                     ZZ
                                                ZX
                                        Z   I     X   I      I    Z
                                                           ZY
                  where      I   k i  is the special moments of inertia of body.  The first index i
                                                                    determines  rotation  of  axis  of
                                                                    body.  The  second  index  k
                                                                    determines  s        rotation  of  the
                                                                    principal axes of inertia
                                                                          These  special  moments  of
                                                                              I
                                                                    inertia      k i      determine  the  total

                                                                    moment  of  inertia  of  a  body
                                                                    about  arbitrary  axis  of  rotation
                                                                    and  create  tensor  of  inertia  of

                                                                    body (tensor – from Latin  –  to
                                    Figure 6.15                     extend):









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