Answers to Selected Problems

Answers to Selected Even Problems

Physics 114

Fall 99

CH.1

48. 5082 ft³, 54. (a) 4.85x10^-6 (b) 3.08x10¹⁶(c) 9.46x10¹⁵ (d) 63240, (e) 3.26

62. 1.16x10¹⁹

CH.2

58. 118 m; 72. (a) 7.7 m/s (b) 6.3m/s (c) 9.8 m/s2; 80. 10.9 m; 110. 13.9 m,

130. 295 m/s

CH.3

70. 408 m; 102. 23.8 m/s; 106. 4^th step, x= 1.15 m, y= 0.72 m

CH.4

42. (a) 2.6I - 0.5 j, (b) -26I + 5j; 52. (a) 3821 N, (b) 4300 N; 80. 32.7 N

CH.5

18. (a) 0.66, (b) a=2.16 m/s², t=1.36 s; 34. (a) 40 N, (b) 720 N, (c) 7.2 m/s²;

38. (a) a=5.76 m/s², (b) 9 kg, (c) a₁=2.62 m/s², a₂=6.54 m/s², T=98.1 N.

106. (a) 193 N, (b) 51.8 N, (c) 44.8 N, (d) 0.27, (e) 533 N

CH.6

38. (a) 0.625t (b) 3.125t (c) 9.375 W; 46. 10004 W;

58. (a) 392 J (b) 2.45 m (c) 368 J, 24 J (d) 392 J, 19.8 m/s; 90. 5743 m

CH.7

18. (a) 5.2 m, (b) 6.3 m, (c) 9.4 m/s; 24. 1.7x10⁴ N

42. (a) 3.14x10¹⁶ J, (b) 7.5 Mton TNT;

x = (mg Sinq /k) + [(mg Sinq /k)² + (2mgL Sinq /k)]^1/2

CH.8

36. (a) v_c = ( m_b/ (m_g + m_bk)) v_b , (b) zero , (c) distance moved = m_b L / M

40. (a) 43.5 J, (b) 1.5 m/s , (c) both speeds = 3.5 m/s , (d) 36.75 J

48. (a) 6 N.s , (b) 4615 N ; 114. 3.7 m ; 124. 0.50 kg

See 114T2example.html for a previous second Phys 114 test.

CH.9

10. (a) 0.588 rad/s², (b) 4.71 rad/s; 24. (a) 1.43 kg m², (b) 7.14 Nm;

38. 3.28 x 10^-45 kg m²; 48. (a) 1.12 J, (b) 0.56 kg m², 1.12 J. 60. (a) 3.95 m/s, (b) 49.4

rad/s; 66. (a) 2.77 m/s, (b) 27.7 rad/s, (c) T1=238 N, T2=233.6 N, (d) 1.46 s.

CH.10

34. v₁/v₂ = r₂/r₁; 38. 3w₀/5; 50. v/[md² + (1/12)(M/m)(L²/d)]; 70. 24mt k, 24m k

CH.11

(4) 2.86x10¹²m (14) a. 22.2 hrs, b. 1.24x10⁹ m; (16) 1.99x10³⁰ kg; (20) 2.27x10⁴ m/s; (56) v_c = 2.97x10⁴ m/s, v_e = 4.21x10⁴ m/s

CH.12

(4) 416.5 N, 269.5 N; (40) 2 [1200 b² + 400 a²]^1/2; (72) w₁=1.5 N, w₂=7 N, w₃=3.5 N

CH.13

(10) 108 atmospheres; (12) 4.07 N; (16) 16 cm; (40) 12.7 N, 35.6 N; (80) 11.76 cm;

(92) 0.23 kg

CH.14

(12) a. 12 cm, b. -12 cm, c. 8.48 cm, d. 3.51 cm; (26) 0.42 J

CH.18

(22) Hint: note the slope of the line AB; (40) 152 J; (44) a. 1845 m/s, b. 461 m/s, c. 394 m/s; (48) v_ave = 4.7 m/s, v_rms = 5.09 m/s; (68) 5373 N.

CH.19

(10) Hint: the bullet partially melts; (82) a. 65.2 K, 81.2 K, b. 31.7 atm.L, c. 37.6 atm.L

CH.20

Skip problems of this chapter, do all of Ch. 21 problems!

CH.21

(4) 7.7 cm; (28) 2073 BTU/hr