Chapter 12
 2. (a) zero            (b) zero
    (c) 80 km/h +x dir  (d) 1500 m/s² 
    (e) 80 km/h -x dir  (f) 1500 m/s²
    (g) 80 km/h +x dir  (h) zero
    (i) 160 km/h +x dir (j) 1500 m/s² 
    (k) zero            (l) 1500 m/s²
 4. 1
 6. solid cylinder - you must explain why
 8. (a) 4 N left        (b) 0.6 kg m²
10. (a) mg(R-r)         (b) (Krot/Ktot) = 2/7
    (c) (17/7)mg
14. (a) (0.11 m)omega   (b) 2.06 m/s² left
    (c) 46.8 rad/s² CW  (d) 1.18 s
    (e) 8.60 m          (f) 6.07 m/s
16. (a) 0.885 s         (b) 9.35 J
    (c) 1.41 m/s        (d) 0.120 J
    (e) 442 rad/s       (f) 9.23 J
24. (a) 12 kg m²/s out of page (b) 3 Nm out of page 
28. (a) -(32 kg m²/s)k         (b) -(32 kg m²/s)k
    (c) (12 Nm)k               (d) zero
34. (a) 0.528 kg m²/s
    (b) 440 rad/s
46. (a) 0.933 rad/s     (b) 98 J
    (c) 8.4 rad/s       (d) 882 J
    (e) calculate work done by each skater
        during pull; adding together yields
        784 J, the amount of increase in K
50. 1290 m/s  (this answer was originally posted incorectly)
              (corrected on 4/21)
54. 2.57 rad/s
56. 0.06995 rad/s
58. (a) 1.5 rad/s       (b) angle is 18.6°
Fishbane Problems - Chapter 9
45. (a) 2.13 kg m²
    (b) 8.83 kg m²/s
    (c) 0.885 rev
    (d) 18.3 J
50. (a) no change       (b) changes to 4.65 rad/s
Fishbane Problems - Chapter 10
13. (a) 0.064 kg m²/s in the direction of rotation
    (b) 0.064 kg m²/s in the direction of rotation

Chapter 14
 8. 2.13 X 10^{-8} N
16. (a) 16.5 N  (b) 2.46 times the radius of the Earth
    (I calculated g of the moon from the mass and radius
     data given on page 305.  If you use g moon from 
     page A-4, you will get (a) 17.0 N (b) 2.43 times)
32. (a) 22.2 MJ (b) 69.5 MJ
34. 24.2 km/s
36. (a) 38.3 MJ (b) 1030 km
54. (2pi)sqrt(r³/G(M+(m/4)))
58. (a) 1/2     (b) 1/2    (c) B by 114 MJ
62. (a) 464 kJ  (b) 257
P66. (a) 54,100 km/hr          (b) 38,200 km/h
P74. proof
P88. (a) 2.24 X 10^{-7} rad/s  (b) 89.5 km/s
P90. (a) 18900 km              (b) 756 MJ
     (c) 8.58 X 10^{24} kg
A3. 0.070 N less
Fishbane Problems - Chapter 8
 6. (a) proof
    (b) r1/r2=m2/m1
Fishbane Problems - Chapter 12
35. 2.99 km/s
55. (a) 1660 m
    (b) 2.83 m/s
    (c) yes; 1.76 m/s
Serway Problems - Chapter 12
49. proof - HINT: After writing the 2nd Law for each
    star, write the velocity of each star in terms
    of the radius of that star's orbit and the time
    to go around once, then add the two equations.
Chapter 16
 6. (a) 1230 N/m    (b) 76 N
16. 21.6 cm
18. (a) 24.8 cm     (b) 2.23 Hz
20. (a) 0.500 m
    (b) -0.251 m
    (c) 3.06 m/s
30. (a) 1.11 Hz     (b) 0.050 m
32. (a) 200 N/m     (b) 1.39 kg   (c) 1.91 Hz
34. (a) 7.25 MN/m   (b) 49,416
36. (a) mv/(m+M)
    (b) mv/sqrt((m+M)k)
38. (a) -(80 N)cos((2000 rad/s)t-(pi/3))
    (b) 3.14 ms
    (c) 4 m/s
    (d) 0.08 J
40. (a) 0.735 kg m² 
    (b) 0.024 N m/rad
    (c) 0.181 rad/s
48. (a) 0.869 s     (b) 6.25 cm
52. (a) (2pi)sqrt(((L²/12)+x²)/gx)
    (b) sqrt(1/12)
    (c) proof
58. (a) (r/R)sqrt(k/M)
    (b) sqrt(k/M)
    (c) zero
64. 4.97 cm