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Answers to even problems: Chapter 4 - 8, 10, 12, 18, 30, 32, 34, 40, 42, 50 |
| 8. (a ) 62 degrees above the x-axis (b) 180 (cm) |
| 10. (a) answers in m/s At t = 0 s: 2i + 4j At t = 1 s: 2i + 2j At t = 2 s: 2i + 0j At t = 3 s: 2i - 2j (b) g = 2.0 m/s2. (c) 63.4 degrees above the positive x-axis. |
| 12. (a) 0.0639 s (b) 782 m/s |
| 18. (a) 150i + 100j (b) The displacement vector makes an angle 56.3 degrees East of North or 33.6 degrees North of East. |
| 30. Answers in rad/s2. Between 0 and 2 seconds: -100, Between 2 and 4 seconds: 0 Between 4 and 7 seconds: 50 Note: Beyond 7 seconds the angular acceleration is 0. |
| 32. area under curve = (1/2)(2)(20) + (2)(20) = 60 radians. Thus # revs = 60/6.28 = 9.55 revs. |
| 34. ar = 2.7 m/s2 . at = 1.27 m/s2 . |
| 40. 15 and 75 degrees. |
| 42. (a) -80.8 m (b) 34.4 (m) (c) 50 m/s at an angle of 73 degrees below the axis. |
| 50. d = 3.71 (m) |