Page 594 - Engineering Electromagnetics, 8th Edition
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576                ENGINEERING ELECTROMAGNETICS

                                              2
                                          2
                                                  2 1.5
                  5.23  (a) 289.5 V (b) z/[(x − 1) + y + z ]  −    ( f ) V (φ) = 28.7φ + 194.9V, E =−(28.7)/ρa φ
                                  2
                              2
                                                                                          2
                                      2 1.5
                       z/[(x + 1) + y + z ]  = 0.222               V/m, D =−(28.7  0 )/ρa φ C/m , ρ s = (28.7  0 )/
                                                                        2
                  5.25  (a)4.7 × 10 −5  S/m (b)1.1 × 10 −3  S/m    ρ C/m , Q b = 122 pC (g) 471 pF
                       (c)1.2 × 10 −2  S/m                    6.41  (a) 12.5 mm (b) 26.7 kV/m
                                                                                             2
                                 2
                  5.27  (a) 6.26 pC/m (b) 1.000176                 (c) 4.23 (with given ρ s = 1.0 µC/m )
                                                                              ◦
                                                                                         ◦
                  5.29  (a) E = [(144.9)/ρ]a ρ V/m, D =       6.43  (a) α A = 26.57 ,α B = 56.31 (b) 23.3 V
                                   2
                       (3.28a ρ )/ρ nC/m (b) V ab = 192 V, χ e = 1.56  6.45  (a) 833.3r −.4  V(b) 833.3r −.4  V
                       (c) [(5.0 × 10 −29 )/ρ]a ρ C · m
                  5.31  (a)80 V/m (b) −60a y − 30a z V/m (c) 67.1 V/m  Chapter 7
                                                   2
                       (d) 104.4 V/m (e)40.0 ( f ) 2.12 nC/m (g) 2.97  7.1  (a) −294a x + 196a y µA/m
                                       ◦
                           2
                       nC/m (h)2.12a x − 2.66a y − 1.33a z nC/m 2  (b) −127a x + 382a y µA/m
                                                 2
                       (i)1.70a x − 2.13a y − 1.06a z nC/m ( j)54.5 ◦  (c) −421a x + 578a y µA/m
                  5.33  125a x + 175a y V/m                   7.3  (a)
                  5.35  (a) E 2 = E 1 (b) W E1 = 45.1 µJ, W E2 = 338 µJ       I         a
                                                                        H =      1 −         a φ A/m
                                                                                       2
                  Chapter 6                                                 2πρ       ρ + a 2
                   6.1  b/a = exp(2πd/W)                           (b)1/ 3
                                                                       √
                   6.3  barium titanate                       7.5
                   6.5  451 pF
                                                                                                      2
                   6.7  (a) 3.05 nF (b) 5.21 nF (c) 6.32 nF (d) 9.83 nF   I        2          2
                                                                    |H|=                −
                                                                                           2
                                                                                2
                   6.9  (a) 143 pF (b) 101 pF                            2π    y + 2y + 5  y − 2y + 5
                  6.11  (a) 53.3 pF (b) 41.7 pF                                                       1/2
                                                                              (y − 1)     (y + 1)    2
                  6.13  K 1 = 23.0,ρ L = 8.87 nC/m, a = 13.8m,           +            −
                                                                              2
                                                                                         2
                       C = 35.5pF                                            y − 2y + 5  y + 2y + 5
                                              2
                                 2
                  6.15  (a) 47.3 nC/m (b) −15.8 nC/m (c) 24.3 pF/m            2
                  6.17  Exact value: 57 pF/m                  7.7  (a) H = I/(2π z)(a x − a y ) A/m
                                                                   (b)0
                  6.19  Exact value: 11  0 F/m                7.9  −1.50a y A/m
                  6.21  (b) C ≈ 110 pF/m (c) Result would not change.  7.11  2.0 A/m, 933 mA/m, 360 mA/m, 0
                  6.23  (a) 3.64 nC/m (b) 206 mA              7.13  (e) H z (a <ρ < b) = k b ; H z (ρ> b) = 0
                  6.25  (a) −8V(b)8a x − 8a y − 24a z V/m     7.15  (a)45e −150ρ a z kA/m 2
                                    2
                               2
                       (c) −4xz(z + 3y ) C/m 3                     (b)12.6[1 − (1 + 150ρ 0 )e −150ρ 0 ]A
                            2 3
                                           2
                                       2
                       (d) xy z =−4(e) y − 2x = 2 and              (c)  2.00 [1 − (1 + 150ρ)e −150ρ ] A/m
                         2
                             2
                       3x − z = 2( f )No                               ρ
                                       2
                                                    2
                                                        2
                  6.27  f (x, y) =−4e 2x  + 3x , V (x, y) = 3(x − y )  7.17  (a)2.2 × 10 −1  a φ A/m (just inside), 2.3 ×
                                                                     −2
                  6.29  (b) A = 112.5, B =−12.5or                  10  a φ A/m (just outside)
                                                                            −1
                       A =−12.5, B = 112.5                         (b)3.4 × 10 −1 a φ A/m     −1
                                                2
                                  3
                  6.31  (a) −106 pC/m (b) ±0.399 pC/m (depending on  (c)1.3 × 10  a φ A/m (d) −1.3 × 10  a z A/m
                       which side of the surface is considered)  7.19  (a) K =−Ia r /2πr A/m (θ = π/2)  2
                                                                                      √
                                                                                2
                  6.33  (a) yes, yes, yes, no (b)At the 100 V surface, no  (b) J = Ia r /[2πr (1 − 1/ 2)] A/m (θ< π/4)
                                                                   (c) H = Ia φ /[2πr sin θ] A/m (π/4 <θ <π/2)
                       for all. At the0V surfaces, yes, except for V 1 + 3.                       √
                       (c) Only V 2 is                             (d) H = I(1 − cos θ)a φ /[2πr sin θ(1 − 1/ 2)]
                  6.35  (a) 33.33 V (b) [(100)/3]a z + 50a y V/m  7.21  A/m (θ< π/4)       2
                                                                             3
                  6.37  (a) 1.01 cm (b) 22.8 kV/m (c) 3.15         (a) I = 2πba /3A(b) H in = bρ /3a φ A/m
                                                                             3
                                                                   (c) H out = ba /3ρ a φ A/m
                                   4
                                               3
                  6.39  (a)(−2.00 × 10 )φ + 3.78 × 10 V                       2
                                  4
                       (b) [(2.00 × 10 )/ρ]a φ V/m            7.23  (a)60ρa z A/m (b)40π A(c)40π A
                                 4
                       (c)(2.00 × 10   0 /ρ)a φ C/m 2         7.25  (a) −259A(b) −259 A
                                                                                      2
                                                                               3
                                  4
                       (d) [(2.00 × 10 )/ρ] C/m 2             7.27  (a)2(x + 2y)/z a x + 1/z a z A/m
                       (e) 84.7 nC                                 (b) same as part (a)(c)1/8A
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