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0593_C04*_fm  Page 114  Monday, May 6, 2002  2:06 PM





                       114                                                 Dynamics of Mechanical Systems





                       Problems



                       Section 4.2 Orientation of Rigid Bodies
                       P4.2.1: In Eq. (4.2.3), suppose that the orientation angles are α = 30°, β = –45°, and γ = 60°.
                       Determine the transformation matrix S and verify that S is orthogonal; that is, the inverse
                       S  is equal to the transpose.
                        –1

                       Section 4.3 Configuration Graphs

                       P4.3.1: Consider the configuration graph of Figure P4.3.1. Find the relations between the
                       N  and the n . Express the results in the matrix forms:
                        i         i

                                                    N = S n    and    n = T N
                       Show that:


                                                         ST =    S −1
                                                           =
                                                              T
                                                                     ˆ
                                                                              ˆ
                                                         i   N       N        n       n
                                                             N
                                                               i       i       i       i
                                                         1
                                                        2
                                                         3
                       FIGURE P4.3.1                            θ         θ       θ
                       Configuration graph.                       1         2       3

                       P4.3.2: Repeat Problem P4.3.1 for the configuration graph of Figure P4.3.2.

                                                                      ˆ
                                                         i   N       N        n  ˆ    n
                                                             N
                                                               i       i       i       i
                                                         1
                                                         2

                                                         3
                       FIGURE P4.3.2                             θ        θ       θ
                       Configuration graph.                        1        2       3


                       Section 4.4 Simple Angular Velocity and Simple Angular Acceleration

                       P4.4.1: A flywheel rotating at 400 rpm is brought to rest in 3 minutes by a uniform braking
                       moment. Determine the angular deceleration and the number of revolutions turned
                       through during the braking.
                       P4.4.2: Consider the rotating disk D of Figure P4.4.2 where θ is the rotation angle of D.
                       Let AB be a line scribed on D, and let φ be the angle AB makes with a fixed horizontal
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