COLM-08-ANSWERSHEET

1. (c) 2. (b) 3. (c) 4. (d) 5. (b) 6. (b) 7. (a) 8. (d) 9. (c) 10. (b) 11. (c) 12. (d) 13. (a) 14. (a) 15. (d) 1. (a) 2. (b) 3. (d) 4. (b) 5. (c) 6. (b) 7. (b) 8. (a) 9. (a) 10. (a) 11. (c) 12. (c) 13. (b) 14. (c) 15. (c) 1. 6 cm. along O O from the sphere of smaller radius. (1 e)u2 sin 2 2. g 4. 5 m/sec. 5. 10 2 m / sec. at 45º with x-axis. 9 1 6. 2 100 7. 3 metre 8. t = 155 second v = 2681 m/s. 9. mg 11. 18.29 m/sec2. 13. momentum is conserved. 14. bob will not rise because whole momentum is transferred to the body at rest. 15. speed will remain constant. SUBJECTIVE LEVEL - II 2. (i) murel m  M (ii) ML m  M 2u sin   1  u2 sin 2 3. (i) g  1 e  (ii) g(1 e) (iii)   tan1(en tan ) 4. m2   M 2 5.  M  m  l 6. 3mv2 7. 0.167 N-s 1 M2 mV2 8. 2 (m  2M)2 d 9. 1  e2 10. Vsphere= V(eM  msin2 ) (M  msin2 ) mvsin (1  e) Vwedge= (M  msin2 ) . SUBJECTIVE LEVEL - III Mv2 h 2g(M  m) 2 2. hmax  h (m  M)2 3. V  2m2 2gr 1 max m  m 1 2 4. VA  23.2 m / s V   41.9 m / s 40.3º 55.6º 5. , Mx m left to the line of fall 6. (a) l   m l M  m (b) F   mM dv M  m dt 7. x  12 d 13 2m2gh cos2  8. V  (M  m)(M  msin 2 ) 9. VA  3 u ; 4 VB  7 u ; 4 J  3 m u 4 10. → VA  1 ˆi  7ˆj; → VB  1 (ˆi  9ˆj) . 4 PROBLEMS 1. t0  12s v = 15.75 m/s 2. (a)   45º (b) v = 2 m/s 3. e = 0.84 M  15.12 kg 4. (a) v0  (b) x  6d .

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