Physics 9A (Summer 1998) - Answers to Even Numbered Problems

• HW #4 - for quiz 7/24/98
  • 6.46 - 4.61 x 10⁸ J
  • 6.50 - cos(theta2) = 1 - (L/(L-x))(1 - cos(theta1))
  • 6.56 - -kA²/2 - aA³/3
  • 6.76
    • a. F(y) = uyg
    • b. W = MgL/2
    • c. U = MgL/2
• HW #5 - for quiz 7/31/98
  • 7.32
    • a. 1.4 v-zero; 45⁰
    • b. elastic
  • 7.60
    • a. 0.818 m/s
    • b. 0.818 m/s
    • c. 0.818 m/s
    • d. -1750 N
  • 7.70 - 9.9 x 10⁵ N
  • 8.38
    • a. plane veers right
    • b. down
  • 8.50
    • a.
      • L_ver = -3.09 kg-m²/s
      • L_hor = 5.36 kg-m²/s
    • b. 14.7 N-m
  • 8.86
    • a. T(1 - 2r/R)/3
    • b. 2T(1 + r/R)/3m
    • c. r/R > 1/2
    • d. direction of T