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Chapter 28
50.  (a) by integration, U_C = (1/2)C(EMF)² and
energy out from battery = C(EMF)²
(b) by integration, heat from resistor = (1/2)C(EMF)²
52.  2.35 MOhms
Fishbane Problems - Chapter 28
57.  proof
Chapter 31
8.   0.452 V
12.  (a) t=0, B=126 microT;
t=0.5s, B=0;
t=1s, B=-126 microT
(b) 50.3 nV
14.  15.5 microC
18.  (a) f  (b) pi²a²Bf
22.  (a) 598 nV  (b) CCW
28.  v=mgR/B²L²
30.  (a) 85.2 Wb
(b) 56.8 V
(c) n=1
32.  path 1, -1.07 mV; path 2, -2.40 mV; path 3, 1.34 mV
34.  0.151 N/C
38.  (a) (mu0)i/W  (b) (mu0)(pi)R²/W
54.  just closed (a) 2 A (b) 0   (c) 2 A
(d) 0    (e) 10 V  (f) 2 A/s
t=infinity  (a) 2 A (b) 1 A (c) 3 A
(d) 10 V (e)  0    (f) 0
58.  (a) 238.7 W  (b) 154.8 W  (c) 393.5 W
60.  (a) 18.7 J   (b) 5.10 J   (c) 13.6 J
62.  5.58 A
66.  (a) 1.26 mT  (b) 0.628 J/m³
72.  (mu0)Nn(pi)R²  plus explanation
74.  ((mu0)(N1)(N2)h/2(pi))ln(b/a)
P90. (a) 43.9 Mm/s² to the right
(b) zero
(c) 43.9 Mm/s² to the left
Fishbane Problems - Chapter 33
46.  DiffEq is -I(t)R - L(dI/dt) = 0
Chapter 32
28.  (a) 1.89 pT
(b) graph; at 10 cm, B = 0.565 pT
30.  750 kV/s
32.  7193 GV/(ms)
34.  (a) 21.2 nA down  (b) CW from above
38.  (a) (4/3) A  (b) at R/4 and at 4R
Chapter 33
12.  (a) 3.6 mH  (b) 1326 Hz  (c) 189 microseconds
32.  0.6 A for all frequencies
34.  (a) 5.22 mA  (b) zero    (c) 4.52 mA
36.  (a) 39.1 mA  (b) zero    (c) -33.9 mA
44.  (a) 16.6 Ohms  (b) 422 Ohms  (c) 521 mA
(d) 33.2 Ohms  (e) 408 Ohms  (f) 539 mA
50.  100 V  (you must carefully explain why)
52.  (a) taking energy    (b) supplying energy
60.  (a) 76.4 mH  (b) yes; 17.8 Ohms; resistor would
consume energy, not store it
G1.  proof
G2.  proof
G3.  proof
G4.  proof
Chapter 34
2.   (a) 4.71 mHZ  (b) 212 s
6.   4.74 m
14.  1.19 MW/m²
16.  Bmax = 3.42 microT; Emax = 1.03 kV/m
34.  4.55 x 10^-4
38.  19.0 W/m²
40.  (a) 15.9%  (b) 84.1%

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