Fishbane Problems - Chapter 8
 6. (a) proof
    (b) r1/r2=m2/m1
Chapter 9
 2. Taking 27.3 days to go around once yields a = 2.73 mm/s²
    and the gravitational field strength (acceleration due to
    gravity) at the Moon's location is 2.69 mm/s² (the Moon's
    orbit is actually elliptical so we don't expect perfect 
    agreement).
 6. 10.0 m/s²
26. proof
34. 4.48 km/s
40. open -  you must explain why
56. 4.59 and 14.2 km/s
58. 4.17 km/s
Chapter 12
24. (a) 2ml²   (b) ml²
40. 265 N⋅m
42. 0.355
44. 1200 s
46. (a) 15.1 MW   (b) 40.8%
56. 1.16 m
60. (5/7)h
68. 32.9 m
Serway Problems - Chapter 12
41.  (a) v_relative = sqrt(2G(m_1+m_2)/d)
     (b) K_1 = 1.07 x 10^32 J; K_2 = 2.67 x 10^31 J
49. proof - HINT:  Write the 2nd Law for each star, 
    then substitute for the speed of each star in 
    terms of the radius of that star's orbit and the 
    time to go around once.  Finally, add the two 
    equations.
Fishbane Problems - Chapter 12
35. 2.99 km/s
55. (a) 1660 m
    (b) 2.83 m/s
    (c) yes; 1.76 m/s
Chapter 13
12. (a) (8.10 N⋅m)k  (b)  (14.7 N⋅m)k
28. (a) 14.2 kg⋅m²/s in the direction of rotation
    (b) 56.9 N⋅m in the direction of rotation
38. 63.0%
52. 2.81 X 10^7 kg
    Hint:  Assume the direction of rotation is not changed
           by the collision.
56. Answer to Hint:  Both E and L are conserved in this explosion.
    (a) (deltax)(sqrt(kI/m(I+mb²)))
    (b) b(deltax)(sqrt(km/I(I+mb²)))
Chapter 14
28. (a) 1.30 kN   (b) 1.94 kN
30. Yes; 79.3 kg
42. 22.8 kN
60. 24.0°
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
Halliday 2nd Ed Problems - Chapter 12
23. (a) mg(R-r)    (b) (Krot/Ktot) = 2/7     (c) (17/7)mg   
    Note: The assumption that R>>r is not necessary.
25. (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
HRW PROBLEM SUPPLEMENT #1 - 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
15  (a) 12.5 cm/s^2  (b) 4.38 s
    (c) 54.8 cm/s    (d) 0.0180 J
    (e) 171 rad/s    (f) 1.39 J
PROBLEM G1 - replaced by P 12:15
    (a) (g)sin(theta)/1.53
    (b) (g)sin(theta)cos(theta)/1.53
    (c) 45° - you must explain why
PROBLEM G2
    0.070 N less
Halliday 2nd Ed Problems - Chapter 14
 3. (a) 1230 N/m    (b) 76 N
14. (a) -(80 N)cos((2000 rad/s)t-(pi/3))
    (b) 3.14 ms
    (c) 4 m/s
    (d) 0.08 J
15. (a) 200 N/m     (b) 1.39 kg   (c) 1.91 Hz
40. (a) 24.8 cm     (b) 2.23 Hz
55. (a) 0.500 m
    (b) -0.251 m
    (c) 3.06 m/s
Chapter 15
32. (2pi)sqrt((R/g)(1+(M/2m)))  -  in 31 there
    is also a torque about the wheel CM due to
    friction with the ground
34. proof - you must write the 2nd Law and
    use it to obtain the diff eq from which
    you can read off the angular frequency
56. 1.11 Hz
58. 1.53 s
60. 5.00 N⋅m/rad
69. NOTE: To get the book's answer, you must assume
    that the collision occurs at the earliest possible
    positive time.  Also note that even though the
    net external x force is not zero, our justification 
    for using momentum conservation in this problem is 
    an assumption that the collision forces are much
    greater than the spring force.
HRW PROBLEM SUPPLEMENT #1 - CHAPTER 16
34. (a) 7.25 MN/m   (b) 49,416