Kinematics-08-ANSWERSHEET

ANSWERS OBJECTIVE LEVEL - I 1. (c) 2. (d) 3. (c) 4. (d) 5. (c) 6. (a) 7. (a) 8. (c) 9. (b) 10. (c) 11. (b) 12. (d) 13. (c) 14. (b) 15. (d) OBJECTIVE LEVEL - II 1. (d) 2. (c) 3. (d) 4. (c) 5. (c) 6. (d) 7. (a) 8. (b) 9. (b) 10. (d) 11. (c) 12. (c) 13. (d) 14. (c) 15. (d) 16. (a) 17. (b) 18. (b) 1. (a) y  a sin ωx u0 SUBJECTIVE LEVEL - I (b) 2. 20 ˆi  10 2  3.   due north east     4. 26.64 m / s , 67.69º 5. 1: 3, 1:1 6. 67º54’ or 48º 40’ 7. 13.45 m, 16.35 m, 5.66 m 8. 2 m / s 2 , 70 m / s 3 3 10. 19.6 m 11. 100, zero 12. 6.17 sec. 13. (i) 746.82 m (ii) 85.55 m/s 15. (a) 82 m (b) LEVEL - II 19 m/s (v1  v 2 ) 2 1. 2(a  a ) 2 3. 4. a n  1 a t av 2  bv1 5. 6. 2.5 m 7. 245 m, 1697.4 m, 1200 m 8. (a) Infinity (b) 60 km. 10. u2 cos2  . gcos3 / 2 LEVEL – III 1. 6 m d 2. 2 3. t  2v 0 sin(1  2 ) g(cos 1  cos 2 ) , 10.7 sec . 4. 7.28 m/sec , 1 sec. 5. 28.2 m/s,   45º . n 8. 9. (a) 10 m/s (b) 2 sec. (c) 5 m (d) 16.25 m (e) 20 m.  a  2 10. (a) x   y  2v0  a2v y av2 (b) a  av , a  , a  net 0 t n PROBLEMS 1. (a) 45º (b) 2 m/s 2. (a) u 2 sin 2 g cos  (b) v  u cos(  ) cos  3. (a) 1 second (b) (5 m, 5m) 4. 5. (a) v = – 1 m/s (b) t = 1.48 sec.

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