Page 595 - Engineering Electromagnetics, 8th Edition

APPENDIX F Answers to Odd-Numbered Problems 577

2
7
6
7.29 (a)1.59 × 10 a z A/m (b)7.96 × 10 ρa φ A/m, 8.29 10.5 mA
2
10ρa φ Wb/m (c)asexpected (d)1/(πρ)a φ A/m, 8.31 (a)2.8 × 10 −4 Wb (b)2.1 × 10 −4 Wb
2
µ 0 /(πρ)a φ Wb/m (e)asexpected (c) ≈ 2.5 × 10 −4 Wb
7.31 (a)0.392 µWb (b)1.49 µWb (c)27 µWb 8.33 (a)23.9/ρ A/m (b)3.0 × 10 /ρ Wb/m 2
−4
7.35 (a) −40φ A(2 <ρ < 4), 0(ρ> 4) (c)5.0 × 10 −7 Wb
−4
2
(b)40µ 0 ln(3/ρ)a z Wb/m (d)23.9/ρ A/m, 6.0 × 10 /ρ Wb/m ,1.0 × 10 −6
7.37 [120 − (400/π)φ]A (0 <φ < 2π) Wb (e)1.5 × 10 −6 Wb
7.39 (a) −30a y A/m (b)30y − 6A 8.35 (a)20/(πr sin θ)a φ A/m (b)1.35 × 10 −4 J
2
(c) −30µ 0 a y Wb/m (d) µ 0 (30x − 3)a z Wb/m 8.37 0.17 µH
2
7.41 (a) −100ρ/µ 0 a φ A/m, −100ρa φ Wb/m 2 8.39 (a)(1/2)wdµ 0 K J/m (b) µ 0 d/w H/m
0
200 2 (c)
= µ 0 dK 0 Wb
(b) − a z A/m (c) −500 MA (d) −500 MA
µ 0
7.43 8.41 (a)33 µH(b)24 µH

µ 0 I ρ 2 5a 8.43 (b)
A z = − 25 + 98 ln Wb/m
96π a 2 ρ 2W H
L int =
I 2
Chapter 8 4 2 2 4 4
8.1 (a)(.90, 0, −.135) (b)3 × 10 a x − 9 × 10 a z m/s = µ 0 d − 4a c + 3c + 4c ln(a/c) H/m
4
5
2
2 2
(c)1.5 × 10 −5 J 8π (a − c )
8.3 (a) .70a x + .70a y − .12a z (b) 7.25 fJ
8.5 (a) −18a x nN (b)19.8a z nN (c)36a x nN Chapter 9
8.7 (a) −35.2a y nN/m (b)0(c)0 9.1 (a) − 5.33 sin 120πt V(b)21.3 sin(120πt)mA
8
5
8.9 4π × 10 −5 N/m 9.3 (a) − 1.13 × 10 [cos(3 × 10 t − 1)
8
8.13 (a) −1.8 × 10 −4 a y N · m 9.5 − cos(3 × 10 t)]V(b)0
(b) −1.8 × 10 −4 a y N · m (a) −4.32V(b) −0.293 V
(c) −1.5 × 10 −5 a y N · m 9.7 (a)(−1.44)/(9.1 + 39.6t)A 1
1
8.15 (6 × 10 −6 )[b − 2 tan −1 (b/2)]a y N · m (b) −1.44[ 61.9 − 39.6t + 9.1 + 39.6t ]A
8
3
8.17 w/w = m/m = 1.3 × 10 −6 9.9 2.9 × 10 [cos(1.5 × 10 t − 0.13x) −
8
8.19 (a)77.6ya z kA/m (b)5.15 × 10 −6 H/m cos(1.5 × 10 t)] W 2 5

10

5
(c) 4.1 (d) 241ya z kA/m (e)77.6a x kA/m 2 9.11 (a) ρ cos(10 t)a ρ A/m (b)8π cos(10 t)A
5
2
( f ) 241a x kA/m (g) 318a x kA/m 2 (c) −0.8π sin(10 t)A(d) 0.1
8
8.21 (Use χ m = .003) (a) 47.7 A/m (b) 6.0 A/m 9.13 (a) D = 1.33 × 10 −13 sin(1.5 × 10 t −
2
(c) 0.288 A/m bx)a y C/m , E = 3.0 × 10 −3 sin(1.5 ×
8
2
8.23 (a) 637 A/m, 1.91 × 10 −3 Wb/m , 884 A/m 10 t − bx)a y V/m
8
2
3
(b) 478 A/m, 2.39 × 10 −3 Wb/m ,1.42 × 10 A/m (b) B = (2.0)b × 10 −11 sin(1.5 × 10 t − bx)a z T,
8
2
3
(c) 382 A/m, 3.82 × 10 −3 Wb/m ,2.66 × 10 A/m H = (4.0 × 10 −6 )b sin(1.5 × 10 t − bx)a z A/m
8
−6 2
2
8.25 (a)1.91/ρ A/m (0 <ρ < ∞) (c)4.0 × 10 −1 b cos(1.5 × 10 t − bx)a y A/m
√
(b)(2.4 × 10 −6 /ρ)a φ T(ρ< .01), (d) 5.0m
10
(1.4 × 10 −5 /ρ)a φ T(.01 <ρ <.02), 9.15 B = 6 × 10 −5 cos(10 t − βx)a z T, D =
2
10
(2.4 × 10 −6 /ρ)a φ T(ρ> .02) (ρ in meters) −(2β × 10 −10 ) cos(10 t − βx)a y C/m ,
10
8.27 (a) −4.83a x − 7.24a y + 9.66a z A/m E =−1.67β cos(10 t − βx)a y V/m,β =
(b)54.83a x − 22.76a y + 10.34a z A/m ±600 rad/m
(c)54.83a x − 22.76a y + 10.34a z A/m 9.17 a = 66 m −1
9
(d) −1.93a x − 2.90a y + 3.86a z A/m 9.21 (a) π × 10 sec −1
(e) 102 ( f )95 ◦ (b) 500 sin(10πz) sin(ωt)a ρ V/m
◦
ρ