Modern Physics-08-ANSWERSHEET

ANSWERS OBJECTIVE UNSOLVED LEVEL – I 1. (d) 2. (d) 3. (c) 4. (d) 5. (d) 6. (a), (b), (c), (d) 7. (b) 8. (d) 9. (d) 10. (c) 11. (d) 12. (d) 13. (a) 14. (c) 15. (b) OBJECTIVE UNSOLVED LEVEL – II 1. (d) 2. (b) 3. (a) 4. (c) 5. (a) 6. (b) 7. (a) 8. (c) 9. (a) 10. (d) 11. (a) 12. (b) 13. (d) 14. (b) 15. (c) SUBJECTIVE UNSOLVED (C.B.S.E.) LEVEL – I 1. 6572 Å, 4870 Å, 4348Å, 4109Å. 2. MeV MeV 3. m 4. (i) 1225Å (ii) 48 eV (ii) 122 V . 5. 0.27Å 6. (a) + 3.4 eV (b) –6.8 eV (c) (b) is change (d) 1217 Å. 7. (a) 27.6 keV (b) of the order of 30 kV 8. 9. Q MeV 10. MeV MeV. SUBJECTIVE UNSOLVED LEVEL – II 1. 2. 123, 2.86 and 0.186 pm 3. 0.45 KeV 4. 39.2 MeV, 5.6 MeV 5. 2.21 MeV 6. (a) (b) kg/day (c) 1264 kg 7. (a) (b) 0.028 min-1(Approx) (c) 25 min (approx) 8. (a) (b) 64 min. 9. 1800y 10. 11. (a) (b) (c) 0.248 Å 12. 13. (i) 3.4 eV (ii) Å 14. (i) 14.43 sec (ii) sec. 15. (a) per sec (b) 285.1 (c) 111 sec. SUBJECTIVE UNSOLVED LEVEL – III 1. (a) (b) 2. 3. 51.4%, 2.13%, 46.45%. 4. (a) A = 232, Z = 90 (b) 5.336 MeV, 7.86 MeV 5. Å 6. E = 150.9 eV 7. (i) m (ii) m 8. Nm-2. 9. , pm m/s eV , eV V , V , nm 52.9 2.18 13.6 13.6 13.6 10.2 121.5 26.5 4.36 54.5 54.5 54.5 40.8 30.4 10. (a) 0.285 pm, 2.53 KeV, 0.65 nm (b) 106 pm, 6.8 eV, 0.243 11. s. 12. 1.342 kg 13. 3.125 × 1016 kg. 14. Joule second. 15. = 0.148 metre. SUBJECTIVE UNSOLVED LEVEL 1. watt 2. (a) (b) . 3. (a) (b) . 4. Kg 5. a.m.u. 6. (i) (ii) (iii) , . 7. (a) (b) 8. 9. sec. 10. 11. 3.861 12. eV.

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