Page 65 - Circuit Analysis II with MATLAB Applications
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Solutions to Exercises


                                       dv         i 0      6
                                                  L
                                       -------- C  =  ------------ =  ---------- =  24   (4)
                                        dt         C      14
                                                           e
                                           t =  0
           From (3) and (4)
                                                k – – 2k =  24   (5)
                                                 1
                                                     2
           and from (2) and (5) k =  48   and k =  – 36 . By substitution into (1) we get
                                1
                                            2
                                                         t –
                                             v t   =  48e – 36e – 2t
                                              C
           Then,
                                                                      2
                                                     di              d i
                                                                        C
                                                      L
                              v AB  =  v t   –  v t   =  L------- – v t   =  LC ---------- –  v t
                                                                            C
                                      L
                                            C
                                                           C
                                                     dt
                                                                       2
                                                                     dt
                                                                t –
                                  =  0.5 ------- 48e –   §  d 2  t –  36 e    – 2t ·  – 48e – 36 e – 2t
                                        ©  dt 2          ¹
                                                            t –
                                  =  0.5 48e –   t –  144 e    – 2t  –  48e – 36 e – 2t
                                                           t –
                                          t –
                                  =  – 24e – 108e – 2t  =  – 24 e +  4.5e    – 2t





































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