NSTSE Sample Paper Solutions Class 11 PCM

UNIFIED COUNCIL A n I S O 9 0 0 1 : 2008 C e r t i f i e d O r g a n i s a t i o n Test Assess Achieve NATIONAL LEVEL SCIENCE TALENT SEARCH EXAMINATION Solutions for Class : 11_PCM MATHEMATICS Therefore, the graph is the interior of a 2 triangle including the points on the sides. 1. (B) Since x + 1 = 0  x = + i .  4. (C) The required number 3 3 3 3 3 3 1 1 +2 1 +2 +3 2. (B) Let P (n): + + = coeff.of x 2m in ( x0 + x1 + ..... + x m )4 1 1+ 3 1+3+5 .......n terms) 4 2m  1  x m+1  3 3 3 = coeff.of x in   1 + 2 + ..... + n  P (n):   1 x  1 + 3 + 5...(n terms) = coeff.of x2m in (1  x m+1 )4 (1  x)4   n3   P (n):   2   n  = coeff.of x2m in (1  4 x m+1 + 6 x2m+2 + ...)  1 n 2 (n + 1)2   ( r + 1) ( r + 2) (r + 3) r   P (n):     1 + 4 x + ... + x + ...  4 n2   3!  1 (2 m + 1) (2 m + 2) (2 m + 3) (m + 1) (m + 2)  P (n): 4  (n2 + 2n + 1) = 6 4m 6 (m + 1) (2 m2 + 4 m + 3) 1 =  P (n): 4  n 2 + 2 n +  1 3 5. (A) With z = x + iy, 1  n (n + 1) 1   P (n):  + n (n + 1) (2n + 1) + n  1 1  x  iy 1 y 4 2 3  we have   i 1z 2  2x 2 2  2x 1  P (n): n {3 (n + 1) + 2 (n + 1) PHYSICS 24 (2n + 1) + 6} 6. (C) It falls with terminal velocity. (i.e., acquires a constant velocity) 1  P (n): n (2n 2 + 9n +13) 7. (C) The pressure inside the soap bubble is 24 more than that outside it. 3. (B) (B) 8. (C) The total momentum of the ball and the Y earth is conserved. 9. (A) Viscous force is temperature dependent 3 and velocity dependent. 0=x X 10. (B) If the force of cohesion is greater than O 4 y=0 adhesion, then the liquid will not wet the solid. website : www.unifiedcouncil.com 1

CHEMISTRY 15. (C) In option (A) No violation of any rule 11. (D) All the given mixtures form buffer In option (B) Violation of Aufbau principle solutions. In case of (II) sodium acetate In option (C) Violation of both Aufbau reacts with HCl to form CH3COOH and principle & Hund’s rule. NaCl. In option (D) V iolation of Aufbau principle. 12. (B) For the given reaction, CRITICAL THINKING (i)  H is negative 16. (A) (ii)  S is negative 13. (A) Exhaust system in limekilns drive away 17. (D) CO 2 formed so that the equilibrium 18. (B) shifts towards forward reaction. 19. (A) 14. (B) HCl, a strong acid, decreases the sulphide ion concentration by common 20. (B) ion effect. Secondly, dil. HCl is used to keep the sulphide on concentration at a minimum level. Thus, products of their respective sulphides precipitate out. website : www.unifiedcouncil.com 2