Errata for Wentworth, Applied Electromagnetics: Early Transmission Lines Approach
Updated 3/13/15
1. FRONTFLAP: The expression in Table 2.1 for the distributed capacitance of Coaxial
Cable should be changed to:
2
C' 
ln  b a 
2. BACKFLAP: The equations for curl in cylindrical and spherical coordinates should be
replaced with the equations on page 615:
cylindrical
1   (  A ) A 
 1 Az A 
 A Az 

a


a


az



 z  
  
 
   z 


A  
spherical
 A 
1  1 Ar  (rA ) 
1   ( rA )  ( Ar ) 
  (sin  A ) A 

ar  

a  

a



r sin  

 
r  sin  
r 
r  r
 
1
3. Page 16: in MATLAB 1.3, the words “Version 1:” and “Version 2:” should be in
Times font to indicate they are not part of the MATLAB program.
4. Page 20: just below (1.10), change “trace leads” to “trace lags”.
5. Page 24-25: under variables, change phi and phir to phase shift, not phase constant
6. Page 26: equation (1.20) should read: re j  r 
7. Page 29: In Drill 1.9, change the part (c) angle from 53° to 37°.
8. Page 34: near bottom of page, change “…theory of Section 2.6…” to “…theory of
Section 6.4…”
9. Page 37: The expression in Table 2.1 for the distributed capacitance of Coaxial Cable
should be changed to:
2
C' 
ln  b a 
10. Page 94: in the code, change “Zo=50” and “ZL=0” to “Ro=50” and “RL=50”,
respectively.
11. Page 96: in Figure 2.44, change Zo to Ro
12. Page 109: Problem 2.15, change 2.25 ns to 6.25 ns.
13. Page 110: in Problem 2.23, change the amplitude of vs from 2.0 to 6.0.
14. Page 120: in Drill 3.2, answer for (d) is: A AB  A AC  4a y  3a z
15. Page 142: in Example 3.8 problem statement, s = 10.0 nC/m2
16. Page 157: at end of page, change to “D = D()a.”
17. Page 161: last answer in Drill 3.18 is in ar direction, not az.
18. Page 180: in (3.84), change L to L.
 Vab L  I S 
19.Page 181: Equation (3.95) should be: P   E Jdv  
 dz   dS 
 L 0  S 0 
20. Page 194: change the 2nd equation on the page to: A 
Va
 1b    1 a 
 ab  Vab
21. Page 194: in Drill 3.31, answer should be: E  
 2 ar
 b  a  2r
22. Page 194: equation listed as (3.119) is actually equation (3.121)
23. Page 199: near the end of Example 3.29, change “E = 1.2 kV” to “E = 1.2 kV/m”.
24. Page 203: In Problem 3.14(c), change the question to ask for mass rather than weight.
25. Page 223: Near top of Example 4.4, change “= Kzdxdzaz” to “= Kzdxdzaz”.
26. Page 243: caption for Figure 4.29 should be changed to: “Figure used to find the
magnetic force exerted by the field of I1 on each arm of a square loop of current I2.”
27. Page 244: last part of the top equation should be: 
o I1I 2  yo  w 
ln 
 az
2
 yo 
28. Page 247: in the first paragraph, line 4, change “perpendicular magnetic force” to
“perpendicular magnetic field”.
29. Page 258: change end of equation (4.73) to “  H T2 w ”
30. Page 273: in (4.112), the l in dl should appear bold to indicate a vector
31. Page 305: in Table 5.1, for the integral form of Gauss’s laws, dS should be dS.
32. Page 310: for Drill 5.10 (b), the answer should be in ax direction, not az.
33. Page 313: before (5.62), change “Problem 5.34” to “Problem 5.35”.
34. Page 318: change the wording of Problem 5.27 to read “Suppose in a hypothetical,
nonmagnetic material that E(z,t) = …”
35. Page 322: equation (6.7) should be:  A    A   2 A
36. Page 322: the left side of equation (6.8) should be    E  2E 
37. Page 322: just before (6.10), change Es t to E t
38. Page 345: In the first equation after Example 6.6, change the unit vector from az to ax
39. Page 346: the second half of the equation at the top of the page should be
E
j
 xo e z e j z e  j e  a y

40. Page 354: In equation (6.102), replace 1 with 2.
41. Page 355: IN (6.111) change   Eot to read   Eoi
t
r
42. Page 358: in Drill 6.15, in the problem statement change Pave
to Pave
, and change the
amplitude of Hr from -0.81 to -0.80.
43. Page 375: equation (7.1) should read: f cmn 
1
2 
2
m n
   
 a  b
2
44. Page 381: in (7.16) change superscript on Zmn from TE to TM.
45. Page 382: in MATLAB 7.1, under ‘display results’ change to the following plot and
legend to attain the figure shown in Figure 7.8:
plot(fghz,ZTE,'-.k',fghz,Zof,'-k',fghz,ZTM,'--k')
legend('ZTE11','Zo','ZTM11')
46. Page 383: change “…using (6.56)…” to “…using (2.75)…”
47. Page 388: just above (7.31), change reference to Helmholtz equation from (5.11) to
(6.11).
48. Page 401: change equation (7.88) to  
n1 cos i  n2 cos t
n1 cos i  n2 cos t
49: Page 409: in Table 7.2, change the units for core diameter to m instead of M, and
for attenuation to dB/km rather than dB/kM.
50. Page 422: in Example 7.6, 3rd sentence below (7.112), change tt so the sentence
reads “…we have tt = 10 ns and…”
51. Page 423, near the end of Example 7.7, change t f  0.4 ns to tt  0.4 ns
52. Page 434: change “(see MATLAB )” to “(see MATLAB 8.1)”
53. Page 444: in the first equation of Example 8.2, change 5.8  10 7 to 5.8  107
54. Page 450: in (8.70) change e-j R to e-j r
55. Page 450: below (8.70), the integral from the table of integrals should be changed to
read:  e ax sin  c  bx  dx  …
56. Page 457: change code, 3rd line from the bottom, to read
den(i) = abs(sin(th(i)));
57: Page 484: change Example 8.14 to read:
“…of Example 8.5 emitting 720 mW of power, we have Prec = 3.1 nW. From (8.119) we
solve for Voc as
Voc  4Rrad Prec  4  73   3.1109W   0.95mV
Without impedance matching, we find from (8.121)
25
VL 
 0.95mV   242V
25  73
58: Page 484: Drill 8.11, change answer to 277 V
59: Page 514: In Figure 9.14 caption, change to “…typically very large R.”
60. Page 519: in ML0903, change bar(m,b,’-k’) to bar(m,b)
61. Page 556: sentence near the end of ML10.3 should read “…to distinguish it from
ML0204.”
62. Page 618: Revise ar, a, ax, and ay in the unit vectors table to read:
a r  sin  cos  a x  sin  sin  a y  cos  a z
a  cos  cos  a x  cos  sin  a y  sin  a z
a x  sin  cos  a r  cos  cos  a  sin  a
a y  sin  sin  a r  cos  sin  a  cos  a
63. Page 623: the last integral should be changed from “  e ax cos  c  bx  dx  ” to
e
ax
sin  c  bx  dx 
64: Page 630: for P2.11: (a) 2b = 18 mm,
2
N 
65. Page 635: for P5.9, change answer to Z1   1  Z 2
 N2 
66. Page 635: for P5.33, change last answer to E(  , t )  226sin(3  108 t  10  )a z V m
67: Page 636: for P6.5, units for  are Np/m
68: Page 637: for P6.23, units for H are A/m