Page 495 - Dynamics of Mechanical Systems
P. 495

0593_C13_fm  Page 476  Monday, May 6, 2002  3:21 PM





                       476                                                 Dynamics of Mechanical Systems


                       P13.9.2: See Problem P13.9.2. Let a rod pendulum with length 1 m be displaced 45° and
                       released from rest. Find the period and frequency.
                       P13.9.3: See Problem P13.9.2. Repeat Problem 13.9.2 for initial displacement angles of 60,
                       90, and 135°.
                       P13.9.4: A simple pendulum with length of 2 ft has a bob speed of 8 ft/sec in its lowest
                       (static equilibrium) position (Figure 13.9.4). Determine the amplitude, frequency, and
                       period.







                                                                2 ft




                       FIGURE P13.9.4
                       A simple pendulum.                          8 ft/sec

                       P13.9.5: Repeat Problem P13.9.4 if the pendulum length is 0.5 m and the speed at the
                       lowest position is 3 m/sec.
                       P13.9.6: The low end of a rod pendulum has a speed of 20 ft/sec as it passes through the
                       static equilibrium position as represented in Figure P13.9.6. Determine the amplitude,
                       frequency, and period of the pendulum for a pendulum length of 3 ft.







                                                                 3 ft





                       FIGURE P13.9.6
                       A rod pendulum.                             20 ft/sec


                       Section 13.10  The Method of Krylov and Bogoliuboff
                       P13.10.1: Use the method of Krylov and Bogoliuboff to find an approximate solution to
                       the equation:

                                                             2
                                                               ˙ x p x = 0
                                                     ˙˙ x + ( ε 1 − x ) +  2
                       where ε is a small constant parameter and p is an arbitrary constant. (This is a form of
                       the Van de Pol equation.)
   490   491   492   493   494   495   496   497   498   499   500