Elasticity and Fluid Machanics-08-ANSWERSHEET

ANSWERS OBJECTIVE UNSOLVED LEVEL – I 1. (a) 2. (b) 3. (d) 4. (c) 5. (b) 6. (b) 7. (c) 8. (a) 9. (a) 10. (a) 11. (d) 12. (c) 13. (a) 14. (c) 15. (b) OBJECTIVE UNSOLVED LEVEL – II 1. (a) 2. (c) 3. (c) 4. (b) 5. (c) 6. (c) 7. (b) 8. (c) 9. (c) 10. (a) 11. (c) 12. (b) 13. (d) 14. (a) 15. (b) SUBJECTIVE UNSOLVED (C.B.S.E.) LEVEL – I 1. 1.8 2. m (steel); m (brass) 3. Pa 4. N 5. Pa 6. Nm-1 7. Excess pressure = 310 Pa total pressure Pa 8. 5.8 cm/sec; N. 9. 55 N 10. 0.800 11. Mercury will rise in the arm containing spirit; the difference in levels of mercury will be 0.221 cm. 12. (a) absolute pressure = 96 cm of Hg; gauge pressure = 20 cm of Hg for (a), absolute pressure = 58 cm of Hg, gauge pressure = ¬ – 18 cm of Hg for (b); (b) mercury would rise in the left limb such that the difference in its levels in the two limbs becomes 19 cm. 13. (a) 11.5 kg (b) 10.5 kg. 14. 5.34 mm 15. For the first bore, pressure difference (between the concave and convex side) Pa.Similarly for the second bore, pressure difference = 97.3 Pa. Consequently, the level difference in the two bores is . The level in the narrower bore is higher. SUBJECTIVE UNSOLVED LEVEL – II 1 2.8 N 2 0.20 m. 3 m 4 kg wt. and kg wt. 5 (a) (b) (c) yes, in free fall 6 7 at is m at is m at is m. 8 N/m2 9 = 0.004 m SUBJECTIVE UNSOLVED LEVEL – III 1. 3.71 mm 2 N, m 3 m 4 m 5 8.8 m/s 6 where 7 (a) 1/2; (b) 2; (c) . 8 . 9. 10. SUBJECTIVE UNSOLVED (IIT-JEE) LEVEL 1. (a) (i) d (ii) (d) (i) (ii) (ii) , 2. 3. 4. (a) net force zero (b) h = 025 cm (c) a = g/6. 5. N-S/m2 6. N/m2 7. 8. 9. .

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