Page 340 - Basic Electrical Engineering
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Figure 3.38 Representation of a phasor

                           2
                  Thus, j  can be seen as equal to –1. Therefore, the value of j becomes equal
               to      .
                  Hence,


                              j = +       , 90° CCW rotation from OX-axis


                                                  2
                               2
                              j  = j × j = (     )  = −1, 180° CCW rotation from OX-axis
                               3
                                          3
                              j  = (     )  =      , 270° CCW rotation from OX-axis
                               4
                                                    2
                                          4
                and           j  = (     )  = (−1)  = 1, 360° CCW rotation from OX-axis
                  From above, it is concluded that j is an operator rather than a real number.
               However, it represents a phasor along the Y-axis, whereas the real number is

               represented along the X-axis.
                  As shown in Fig. 3.39 (b), phasor OB can be represented as                    in the

               polar form. In the rectangular form OB is represented as 4 + j3
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