SOLUTION & ANSWER FOR AIEEE-2008

 VERSION – A1

 

[PHYSICS, CHEMISTRY & MATHEMATICS]

 


PART A - PHYSICS

 

1.     A body of mass m = 3.513 kg …….

 

        Ans :  3

 

        Sol:     min (4, 3)

                    = 3

               

2.     Consider a uniform square plate of side …….

       

        Ans :  

 

        Sol:       I = I cm + md2

                      =

                     =

 

3.     The speed of sound in oxygen ……..

 

        *Ans :     1419 m/s

 

        Sol:

               

                =

               

                v He =

                = 1419 m/s

 

                        * None of the given answers matches with our           answer.

 

4.     A thin spherical shell of radius R has ……..

 


        Ans :

 

 

 

        Sol:     E = 0, r < R

                    E = r > R

       

 

 

 

 

 

 

5.     Relative permittivity and permeability of a ……

       

        Ans :   e r = 1.5, m r = 0.5

       

        Sol:     m r < 1 for diamagnetic

                    e r > 1 for all materials             

 

6.     Suppose an electron is attracted towards the ….. 

       

        Ans :   Tn independent of n, rn µ n

 

        Sol:    

                    Ž independent of n

                    mvr =   Ž r µ n

                   

7.     A block of mass 0.50 kg is moving with a speed…

       

        Ans :   0.67 J

 

        Sol:    

                    =

 

8.     A wave traveling along the x-axis is …..

 

        Ans :   a = 25.00 p , b = p

 

        Sol:     a =

                    b = w =

                    Ž a = 25.00 p , b = p

 

9.     A working transistor with its three legs….

 

        Ans :   it is npn transistor with R as base.

 

        Sol:     Emitter to collector will always be non                        conducting.

 

10.  A jar is filled with two non-mixing …….

 

        Ans :   r 1 < r 3 < r 2

 

        Sol:     r 3 floats in r 2 and sinks in r 1

                    = r 1 < r 3 < r 2

 

11.  An athlete in the Olympic games…….

 

        Ans :   2000 J – 5000 J

 

        Sol:     v is of the order of 10 ms- 1 and mass is             around 50 kg Ž 2000 J – 5000 J

 

12.  A parallel plate capacitor with air between……

 

        Ans :   40.5 pF

 

        Sol:     C 1 = 9 ´ 3 ´ 3 = 81

                    C 2 =

                    C = = 40.5 pF

 

13.  The dimension of magnetic field in …….

 

        Ans : MT- 1C- 1

 

        Sol:     F = Bqv

                    [B] =

                    = MT- 1C- 1

 

14.  A body is at rest at x = 0. At t = 0 …….

 


        Ans :  

 

 

 

 

 

        Sol:     x 1 - x2 =

 

 

 

 

 


15.  In the circuit below, A and B represent …..

 

        Ans :   OR gate

 

        Sol:     Either A or B is high, it pulls C high

                    Ž OR gate

 

16.  While measuring the speed of sound ……

 

        Ans :   x > 54

 

        Sol:     Speed increases slightly with                               temperature Ž l increases Ž for second             resonance x > 54

 

17.  Shown in the figure below is a meter-bridge…..

 

        Ans :   220 W

 

        Sol:    

                    R = 220 W

 

18.  A spherical solid ball of volume V is …….

 

        Ans :  

 

        Sol:     Kv 2 = mg - FB

                    = (r 1- r 2) Vg

                    v =

 

19.  A thin rod of length ‘L’ is lying along ……

 

        Ans :  

 

 

 

 

 

 

        Sol:     x cm = =

 

 

 

 

 

 

 


20.  A planet in a distant solar system is ……

 

        Ans :   110 km s- 1

 

        Sol:     v esc =

                    =

                    Ž v2 = 110 km/s

       

21.  An insulated container of gas has two……

 

        Ans :  

 

        Sol:     n 1 CV T1 + n2 CV T2 = (n1 + n2) CV T

                    T =

 

22.  Two full turns of the circular scale …..

 

        Ans :   3.38 mm

 

        Sol:     3 +

                    = 3.38 mm

 

23.  A horizontal overhead powerline is ……

 

        Ans :   5 ´ 10- 6 T southward

 

        Sol:    

 

 

 


                    B = = 5 ´ 10- 6 T

 

24.  An experiment is performed to find …..

 

        Ans :   a vernier scale provided on the                    microscope

 

        Sol:     Vernier scale on the microscope

 

25.  A 5 V  battery with internal resistance …..

 

        Ans :   0.03 A P2 to P1

 

        Sol:     E eff = Ž I = 0.03 A P2 to P1

 

 

 

26.  A capillary tube (A) ……

 

        Ans :  

 

 

 

 

 

 

                    Sol:     Surface tension is lowered.

 

27.  Two coaxial solenoids are made ……

 

        Ans :   2.4 p ´ 10- 4 H

 

        Sol:     M = = 2.4 p ´ 10- 4 H

 

28.  A student measures the focal ….

 

        Ans :  

 

 

 

 

 

 

 

 

        Sol:     u < 0, v > 0

 

29.  This question contains statement – 1

 

        Ans :   Statement – 1 is true, Statement – 2 is               true; Statement – 2 is a correct                                 explanation for Statement -1

 

        Sol:     Gauss law for gravitation

 

30.  This question contains statement - 1

 

        Ans :   Statement – 1 is true, Statement – 2 is               false’

 

        Sol:     BE per nucleon increases for lighter                   nuclei and decreases for heavy nuclei.

 

31.  For current entering ….

 

        Ans :  

 

        Sol:     j ´ 2p r2 = I

                    E = r j =

32.  D V measured between B and C is

       

        Ans :  

 

        Sol:     D V =

                    =

 

33.  If a strong diffraction peak is observed when        electrons are incident at an angle `i’ -

 

        Ans:    2d cos i = n l dB

 

        Sol:     2d cos i = n l dB

 

34.  Electrons accelerated by potential V are        diffracted from a crystal. -

 

        Ans:    50 V

 

        Sol:    

                    = 50 V

35.  In an experiment, electrons are made to pass     through a narrow slit of

 

        Ans:   

 

 

 

 

 

 

 

 

PART B - CHEMISTRY

 

36.  The ionization enthalpy of hydrogen …….     

 

        Ans:   9.84 x 10 5 J mol–1

 

        Sol :   = 1.312 ´ 106

                          = 1.312 ´   ´ 106

                          = 9.84 ´ 105 J mol–1

 

37.  ….. pairs of species have the same bond order?        

 

        Ans:   CN and NO+

 

        Sol :   Both CN and NO+ contain 14 electrons each and hence they have the same bond order.

38.  …….. a group of the isoelectronic species? 

 

        Ans:   NO + , C22–, CN, N2

 

        Sol :   Total no. of electrons in NO + = 14 (7+8–1), C22– = 14 (6+6+2), CN = 14 (6+7+1) and
N2 = 14 (7+7).

 

39.  Four species are…….

        i.         ii.                    iii.                       iv.

        …… the correct sequence of their acid strength?        

 

        Ans:   i < iii < ii < iv

 

        Sol :   Fluoro sulphonic acid is the strongest, followed by H3O+,  and .

                   i < iii < ii < iv

 

40.  The pKa of a weak acid, HA is ……………… 

 

        Ans:   7.01

 

        Sol :   pH = [pKw + pKa – pKb]

                         =  [14 + 4.8 – 4.78] = 7.01

 

41.  …… decreasing order of priority for the functional groups of …….          

 

        Ans:   - COOH, - SO3H, - CONH2, - CHO

 

        Sol :   Priority order is

                   - COOH > - SO3H > - CONH2 > - CHO

 

42.  ……. CH3MgX with CH3C C–H …….    

 

        Ans:   CH 4

 

        Sol :   CH 3- C ŗ C- H + CH3MgX ®

                                                CH 3- C ŗ CMgX + CH4

 

43.  …….can react with sodium in liquid ammonia

 

        Ans:   CH 3- CH2- C ŗ CH

 

        Sol :   CH 3- CH2- C ŗ CH is a terminal alkyne containing acidic hydrogen. So it reacts with sodium in liquid ammonia forming the corresponding sodium derivative.

       

44.  The vapour pressure of water at 200C is ………

 

        Ans:   17.325 mm Hg

        Sol :   =

                   =

                   17.5 – p = 0.175

                   P = 17.325

 

45.  Gold numbers of protective colloids A, B, C and D …….…

 

        Ans:   A < C < B < D.

 

        Sol :   Lesser the gold number greater is the protective action. Protective action follows the order A < C < B < D.

 

46.  ……. atoms of element Y form ccp …….               

 

        Ans:   X 4Y3

 

        Sol :   = X4Y3

 

47.  …… the industrial preparation of hydrogen from water gas ……..           

 

        Ans:   CO is oxidized to CO 2 with steam in the presence of a catalyst followed by absorption of CO2 in alkali.

 

        Sol :   From water gas (CO + H 2), CO is oxidized to CO2 with steam and which is then absorbed in alkali.

 

48.  …… substituted silane the one ……… to cross linked silicone ……..            

 

        Ans:   RSiCl 3

 

        Sol :   Among the substituted silanes, RSiCl 3 on hydrolysis give rise to cross linked silicone polymers.

 

49.  Amount of oxalic acid present in a solution can ….     

 

        Ans:   reduces permanganate to Mn 2+ .

 

        Sol :   Mn +7 oxidises both  and Cl.

 

50.  Given      = –0.72 V = –0.42 V. The potential for the cell ………..

 

        Ans:   0.26 V

        Sol :   Cell reaction is 3Fe 2+ + 2Cr ® 2Cr3+ + 3Fe

                   E cell =

                          = (0.72 - 0.42) +

                          = 0.3 - 0.04

                          = 0.26 V

 

51.  …… the correct statement?     

 

        Ans:   Chlorides of both beryllium and aluminium have bridged chloride structures in solid phase.

 

        Sol :   Beryllium and aluminium chlorides have bridged structures in solid phase.

 

52.  Identify the wrong statement ………       

 

        Ans:   Ozone layer does not permit infrared radiation from the sun to reach the earth.

 

        Sol :   The incorrect statement is “Ozone layer does not permit I .R radiation from the sun to reach the earth”. Actualy ozone layer prevents u.v. radiation from the sun to reach the earth.

 

53.  The coordination number and the oxidation state of the element …….. 

 

        Ans:   6 and 3

 

        Sol :   en and  are bidendate ligands.

        \ Coordination number of E is 6 and oxidation state of E is 3 (en is neutral and )

 

54.  ……. Octahedral complexes of Co ….   

 

        Ans:   [Co(CN) 6]3‑

 

        Sol :   The strongest ligand is CN and hence D 0 will be the highest for [Co(CN)6]3‑.

 

55.  Larger number of oxidation states are exhibited …..  

        Ans:   lesser energy difference between 5f and 6d than between 4f and 5d orbitals.

        Sol :   The energy difference between 5f and 6d (actinoids) is less than between 4f and 5d (lanthanoids) and hence actinoids exhibit larger number of oxidation states.

56.  ……. no significance for roasting sulphide ores to ……    

 

        Ans:   CO 2 is more volatile than CS2

 

        Sol :   The insignificant statement is ‘CO 2 is more volatile than CS2’.

        The reduction process is based on the thermodynamic stability of the products and not on their volatility.

 

57.  Oxidising power of chlorine in aqueous solution ….  Cl2(g) ……………………Cl(aq)

        The energy involved in the conversion of ………   

 

        Ans:   - 610 kJ mol‑1

 

        Sol :   Energy involved the conversion of
Cl2(g)
®

                                =  - 349 - 381

                                = - 610 kJ mol‑1

 

58.  …… the alkene affords the compound ….    

 

        Ans:   CH 3CHO

 

        Sol :   CH 3- CH=CH- CH3  2CH3CHO.

 

59.  Phenol, when it first reacts with concentrated sulphuric acid …..    

 

        Ans:   *2,4,6-trinitrophenol.

 

        Sol: :         

        * None of the given answers matches with our

         answer.

 

60.  Toluene is nitrated and the resulting ……    

 

        Ans:   mixture of o- and p- bromotoluenes

 

        Sol :

               

 

61.  The organic chloro compound, which …..     

 

        Ans:   CH 3Cl

 

        Sol :   Primary alkyl halides undergo S N2 reaction with inversion of configuration.

 

 

 

 

 

 

 

 

 

 

 

 

62.  The absolute configuration of ………     

 

        Ans:   R, R

 

        Sol :   The absolute configuration of both the carbons are ‘R’.

 

63.  -D-(+)-glucose and -D-(+)-glucose are  

 

        Ans:   anomers

 

        Sol :   a -D(+)glucose and b -D(+)glucose are anomers.

 

64.  The electrophile,  attacks …….  

 

        Ans:  

 

        Sol :   group is a deactivating group.

        Hence the intermediate formed from benzene will have lower energy than that formed from nitro benzene.

 

65.  Standard entropy of X2, Y2 and XY3 …….

 

        Ans:   750K

 

        Sol :   T =

                   D S = - 40 J

                   \ T =

                           = 750K

 

66.  For the following three reactions a, b and c, …..  

 

        Ans :  K3 = K1 K2.

 

        Sol :   The first two reactions are added to get the third reaction, hence K3 = K1 ´ K2.

 

67.  Bakelite is obtained from phenol …..     

 

        Ans:   HCHO

 

        Sol :   Bakelite is a polymer of phenol and formaldehyde.

 

 

 

 

68.  The equilibrium constant and  for ……

 

        Ans:   1 : 36

 

        Sol :   X  2Y, Equilibrium constant =

                   Z  P + Q, Equilibrium constant =

        When the degree of dissociation is the same for the two reactions, then
 =  and  = p2.

                  

                   i.e., ;

 

69.  For a reaction A  2B, rate of ………        

 

        Ans:  

 

        Sol :   For the give reaction,

                   2 X  =

                   or

 

70.  At 800C, the vapour pressure of pure liquid ‘A’ is 520 mm Hg and that of ……..   

 

        Ans:   50 mol percent

 

        Sol :   = 760

                   520X A + 1000(1 - XA) = 760

                   x A =

                   Mole percent = 50

 

PART C - MATHEMATICS

 

71.  Let f : N ® Y be a function defined as ……….

 

Ans: g(y) =

 

        Sol:y = 4x + 3

                x =

                g(y) =

 

 

 

 

72.  Let R be the real line. Consider the following…..

 

Ans: T is an equivalence relation on R but S is not

 

Sol:S = {(x, y): y = x + 1       0 < x < 2

                (x, x) ® x = x + 1 ® not reflexive

                (x, y) ¹ (y, x) ® not symmetric

 

73.  The conjugate of a complex number is …….

Ans: 

 

Sol:

                Conjugate number =

                               =

 

74.  The quadratic equations x2 - 6x + a = 0 and ……

 

Ans: 2

 

Sol:Let a , b be the roots of x2 - 6x + a = 0 and a , g be the roots of x2 - cx + 6 = 0

                        Ž a + b = 6                           a + g = c

                                                     and

                        a b = a                                    a g = 6

                and

                \ a

                \ The first equation is x2 - 6x + 8 = 0

                Ž   2 and 4 are the roots.

                If b = 2, then g =  Ž Not possible, since     roots are integers

                If b = 4 Ž g = 3 Ž possible

                \ The common root is 2

 

75.  Let A be a square matrix all of whose entries……

       

        Ans: If det A = ± 1, then A- 1 exists and all its 
          entries are integers

 

Sol:If det A ¹ ± 1, then det A may be zero Ž A- 1 does not exist.

                When det A = ± 1, then A is orthogonal

        Ž A- 1 = AT Ž A- 1 will have all enteries as integers

 

 

76.  Let a, b, c be any real numbers. Suppose…….

 

        Ans: 1

 

        Sol: x - cy - bz = 0

                - cx + y - az = 0

                - bx - ay + z = 0

                Given that x, y, z not all zero.

                Ž The given homogeneous system has       non-trivial solutions.

                Ž  = 0

                Ž 1(1 - a2) + c(- c - ab) - b(ac + b) = 0

                Ž - a2 - b2 - c2 - 2abc + 1 = 0

                Ž a2 + b2 + c2 + 2abc = 1

 

77.  How many different words can be formed by ……

 

        Ans:        7.6C4.8C4

 

        Sol: 4I, 2p, 4s and 1 M are there in MISSISSIPPI .

                Arrange the remaining 7 letters ®

                * - * - * - * - * - * - * - *

        In the eight places in between (marked as *) we can arrange the 4s’s in 8C4.wsays

                \ Total number of words =

                                                                 = 7.6C4.8C4

 

78.  The first two terms of a geometric progression….

       

        Ans : - 12

 

        Sol: a + ar = 12

                ar 2 + ar3 = 48

                r 2 (a + ar) = 48

                r 2 = 4

                r = ± 2

r = - 2, since terms are alternately positive and negative

                a =

                 

79.  Let f(x) =  ……..

 

        Ans : f is differentiable at x = 0 but not at x = 1

 

        Sol :  f(x) =

               

                        =

                        =

                f’(1) =

                        =

                        =

                does not exist

 

80.  How many real solutions does the equation……..

 

Ans:  1

 

        Sol:f(x) = x7 + 14x5 + 16x3 + 36x - 560

                f'(x) = 7x6 + 70x6 + 48x2 + 30

                        > 0 for all x Ī R

                f(x) is monotonic increasing

                f(x) = 0 has only one real solution

 

81.  Suppose the cubic x3 - px + q has three distinct..

 

Ans: The cubic has minima at  and maxima
          at
-

       

        Sol:f(x) = x3 - px + q

                f'(x) = 3x2 - p

                f”(x) = 6x

                3x 2 = p Ž x = ±

                f(x) is minimum at x =  and

maximum at x = -

 

82.  The value of   is ………..

Ans: x + log

 

        Sol:

                    =

                   =

                  = x + log

 

83.  The area of the plane region bounded by the …..

 

        Ans:

 

        Sol:x + 2y2 = 0 Ž x = - 2y2

                 x + 3y 2 = 1 Ž x = 1 - 3y2

       

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


                Shaded portion is the required area

                Required area =

                                =

                                =

 

84.  Let I =  and J = …….

 

        Ans : I <

        Sol : I =

                        <    

                        < 2

                J =

                        <

                        < 2

                In (0, 1) Ž sin x < x

               

                I <

 

85.  The differential equation of the family of circles…

 

Ans: (y - 2)2 y’2 = 25 - (y - 2)2

 

        Sol : (x - h)2 + (y - 2)2 = 25

                2(x - h) + 2(y - 2) = 0

                (x - h) = - (y - 2)

                Differential equation is

                (y - 2)2 = 25

 

86.  The solution of the differential equation  ……

 

Ans: y = x ln x + x

 

Sol:Put y = Vx

               

                \ V +

                V + = 1 + V

                        x

                \ V = log x + C

               

                y(1) = 1 Ž C = 1

                \  =  log x + 1

                y = xlogx + x

 

87.  The perpendicular bisector of the line segment ...

 

Ans: - 4

 

        Sol : Slope of the line =  = k - 1

                Passes through

                Perpendicular bisector is

                y -  = (k - 1)

                2y - 7 = 2x(k - 1) - (k2 - 1)

                2x(k - 1) - 2y = k2 - 8

                 = - 4

                k 2 - 8 = 8

                Ž k = ± 4

 

88.  The point diametrically opposite to the point
P(1, 0) on the circle……..

 

Ans: (- 3, - 4)

 

Sol:Centre (- 1, - 2) . P(1, 0)

                \ opposite point Q(x, y)

                \ mid point of PQ = Centre

                \   

                x = - 3, y = - 4

                \ Point (