Page 246 - Thomson, William Tyrrell-Theory of Vibration with Applications-Taylor _ Francis (2010)
P. 246

Chap. 7   Problems                                            233


                              7-22  Using area  moment  and  superposition,  determine  M,  and  /?2  for  the  beam  shown  in
                                  Fig.  P7-22.  Let  £/,  = 2El,.
                                                    M
                                               t,
                                       "’Cf
                                               EU         El,
                                                                f f .   Figure  P7-22.
                              7-23  With  loads  m  and  J  placed  as  shown  in  Fig.  P7-23,  set  up  the  equations  of  motion.
                                                              /TI2 '^2 .
                                         %                    1 3
                                              El,        Eh          Figure P7-23.
                              7-24  For the extension of the double pendulum  to the  dynamic problem,  the  actual  algebra
                                  can  become  long  and  tedious.  Instead,  draw  the  components  of  —r  as  shown.  By
                                  taking each  86  separately,  the virtual work equation can be easily determined visually.
                                  Complete  the  equations  of  motion  for  the  system  in  Fig.  P7-24.  Compare  with
                                  Lagrange’s derivation.
















                                                                     Figure P7-24.

                              7-25  Write  the  Lagrangian for the  system  shown  in  Fig.  P7-25




                                                                     Figure P7-25.
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