Rt Solutions-18!12!2011 XIII VXY Paper I Code A

Embed Size (px)

Citation preview

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    1/17

    13th VXY (Date: 18-12-2011) Review Test-5

    PAPER-1

    Code-A

    ANSWER KEY

    CHEMISTRY

    SECTION-2

    PART-A

    Q.1 D

    Q.2 D

    Q.3 C

    Q.4 A

    Q.5 A

    [Only V-Group Batch]

    Q.6 C

    [Only XY Batch]

    Q.6 A

    Q.7 C

    Q.8 B

    Q.9 A

    Q.10 A,B,C,D

    Q.11 A,C,D

    [Only V-Group Batch]

    Q.12 A,B,C,D

    [Only XY Batch]

    Q.12 A,D

    PART-B

    (Only V-Group Batch)

    Q.1 (A) P,Q,R,S,T

    (B) P,Q,R,S

    (C) P,S

    (D) P,R,S,T

    (Only XY Batch)

    Q.1 (A) Q,T

    (B) P,T

    (C) P,S

    (D) R,S

    PART-C

    Q.1 3006

    [Only V-Group Batch]

    Q.2 2345

    [Only XY Batch]

    Q.2 9890

    Q.3 3049

    Q.4 0004

    PHYSICS

    SECTION-1

    PART-A

    Q.1 C

    Q.2 B

    Q.3 D

    Q.4 A

    Q.5 B

    Q.6 A

    Q.7 D

    Q.8 BQ.9 A

    Q.10 A,B

    Q.11 C

    Q.12 B,C,D

    PART-B

    Q.1 (A) P,Q

    (B) P,S

    (C) P,S

    (D) R

    PART-C

    Q.1 0500

    Q.2 0006

    Q.3 0001

    Q.4 0005

    MATHS

    SECTION-3

    PART-A

    Q.1 D

    Q.2 B

    Q.3 B

    Q.4 D

    Q.5 D

    Q.6 B

    Q.7 B

    Q.8 DQ.9 D

    Q.10 B,C,D

    Q.11 B,C

    Q.12 B,D

    PART-B

    Q.1 (A) S

    (B) P,Q

    (C) P

    (D) Q

    PART-C

    Q.1 0002

    Q.2 0006

    Q.3 0002

    Q.4 0010

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    2/17

    PHYSICS

    Code-A Page # 1

    PART-A

    Q.1

    [Sol. P =R

    q2

    R =A

    P

    R8

    q'P

    2

    R' =4A/

    )2( l= 8R ]

    Q.2

    [Sol. T2 =GM

    4 2r3

    G =sR

    3

    4T

    4

    32

    2

    R

    3= 2

    T

    3

    ]

    Q.3

    [Sol. Let T be final temp.

    V1S(TT

    1) + V

    2S(TT

    2) = 0

    T =21

    2211

    VV

    VTVT

    ]

    Q.4

    [Sol. msdt

    dT=A (T4T

    04)

    dtdT

    m1

    Lesser mass cools faster and hollow sphere is having less mass. ]

    Q.5

    [Sol. PV = nRTV

    n=

    RT

    P

    Since temperature in all are same.

    One having more pressure has heightest particle density. ]

    Q.6[Sol. P T3

    P = k3

    nR

    PV

    P2V3 = const. PV3/2 = const. Y = 3/2 ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    3/17

    PHYSICS

    Code-A Page # 2

    Paragraph for question nos. 7 to 9

    [Sol. Q.No. 7 & Q.No. 8

    i

    R

    27 iR

    )27R(i = ..... (1)

    R

    3

    ni

    (ni)i

    i

    iR = 3(n1)i R = 3(n1) ...... (2)

    From (1) and (2)

    (R + 27) = R

    13

    R R = 9 and n = 4 ]

    Q.9

    [Sol.

    378V

    40A

    8 A

    9 27 330

    32A 40A 10A

    9

    9]

    Q.10

    [Sol. g =

    Rrr

    GM

    RrR

    GMr

    2

    3

    (A) r, r2

    < R 2

    1

    FF

    =2

    1

    rr

    (B) r, r2

    > R 2

    1

    F

    F= 2

    1

    22

    r

    r]

    Q.11

    [Sol.

    3F 5F

    30V

    56.25+q1

    56.25+q

    30V

    7F

    q = 56.25 Ci

    q

    q2

    3

    q25.56

    7

    q12

    ..... (1)

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    4/17

    PHYSICS

    Code-A Page # 3

    5

    qq25.56

    7

    q212

    = 30 ..... (2)

    q2

    = 70 ; q1

    =26.25

    q = 43.75 ]

    Q.12

    [Sol.

    A

    10V 2.510

    i = 4A

    Maximum

    A

    10V 2.5

    i = 2A

    Minimum

    ]

    PART-B

    Q.1

    [Sol. (A) .const

    P

    T1y

    y

    P

    T

    y

    1y

    TP

    = const. R

    (B) E = 2/322)Rx(

    kQx

    E

    x

    (C)U

    VR.O.R.I.

    R.O.V.I.

    (D) Speed decreases as infinity does not exist. ]

    PART-C

    Q.1

    [Sol. E =y2 0

    sin =

    y2 0

    22 hy

    h

    Y

    Z

    h

    h(y,0)

    =h8

    0

    y = h ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    5/17

    PHYSICS

    Code-A Page # 4

    Q.2

    [Sol. T = (lx)g ...... (1)T = xg ...... (2)

    l

    x=

    1

    ]

    Q.3

    [Sol. More the resistance less will be power dissipated.

    One should connecte the battery is 6 resistor.

    2

    11V

    ]

    Q.4

    [Sol.

    Kd

    Id2

    2

    2m12

    1 (2) =K

    K =12

    1ml2

    2

    T

    2

    = 5 ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    6/17

    CHEMISTRY

    Code-A Page # 1

    PART-A

    Q.1

    [Sol. 2C (graphite) + O2

    (g) 2CO (g) rH =110.5 2

    CO2(g) C(graphite) + O

    2(g)

    rH = 393.5

    C(diamond) C (graphite) rH = 2

    __________________________________________________

    CO2

    (g) + C(diamond) 2CO(g) rH = + 170.5 kJ/mol Ans. ]

    Q.2

    [Sol. CH2

    = CHCH2I

    )excess(HI

    II||CHCHCH 23 2I

    CH3CH=CH

    2

    HI

    I|

    CHCHCH 33 ]

    Q.3

    [Sol. A : Cr3+ in [Cr(H2O)

    6]3+

    Hyb : d sp

    = 3.89 B.M.

    2 3

    eff

    3d 4s 4p

    B : Cu+ in [Cu(CN)4]3

    Hyb : sp

    = 0

    3

    eff

    3d 4s 4p

    C : V+++ in [V (H2O)

    6]3+

    Hyb : d sp

    = 2.83 B.M.

    2 3

    eff

    3d 4s 4p

    D : Co++

    in [Co(H2O)6]++

    Hyb : sp d= 3.89 B.M.

    3 2

    eff

    3d 4s 4p

    ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    7/17

    CHEMISTRY

    Code-A Page # 2

    Q.4

    [Sol. A CO2 5600 counts 2800 1400

    B CO2 1400 counts

    2 half lives. ]

    Q.5

    [Sol. NO2

    will showI, butOMe will show +M.

    NO2 NO2 OMeNO2

    NO2

    CH CO

    CH

    CH

    O O

    O

    O

    + OH +OH

    CH OH2

    ]

    [Only V-Group Batch]

    Q.6

    [Sol. H3PO2 H3PO4 + PH3

    H3PO

    3

    H3PO

    4+ PH

    3

    H3PO

    4

    P4O

    10+ H

    2O

    HNO2

    NO + HNO3

    H3PO

    4doesn't undergoes disproportionation ]

    [Only XY Batch]

    Q.6

    [Sol. (A) CCl ClCl

    H

    (B)

    C

    C

    O OH

    Cl ClCl

    H H

    Chloral (CCl3CHO) Chloral hydrate CCl

    3CHO . H

    2O

    (C)

    H

    H

    O

    O

    C (D)

    HO

    Cl

    Ortho hydroxy benzaldehyde ortho chlorophenol ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    8/17

    CHEMISTRY

    Code-A Page # 3

    Paragraph for question nos. 7 to 9

    [Sol.(7) M = 0.1

    M =2.11

    strengthvolume

    0.1 =2.11

    V volume strength = 1.12 Ans.

    (8) [Sol. H2O

    2+ 2KI I

    2

    nf= 2 n

    f=1 n

    f=2

    I2

    + hypo 2I

    nf= 2 n

    f= 1

    Eq. H2O

    2= Eq. of I

    2= Eq. Hypo .....(1)

    Eq. Hypo = 200 0.1 = 20

    KIO3

    + KI I2n

    f= 5 n

    f= 1 n

    f= 5/3

    5 mm of KIO3

    =3

    5 mm of I

    2....(2)

    from equation (1) 2 mm of I2 = 20mm of I

    2= 10

    mm of KIO3

    =3

    52=

    3

    10Ans.

    (9) N1V

    1= N

    2V

    2

    V 0.1 2 = 0.1 200

    V = 100 ml ]

    Q.10

    [Sol. (A)

    H

    exp

    ring

    ringexp.

    OH

    OH2

    (B) H

    OH2

    OH

    (C) H

    then same as (A)

    (D) H

    OH2

    OH

    ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    9/17

    CHEMISTRY

    Code-A Page # 4

    Q.11

    [Sol. (A) Due to high value of Zeff

    in Ir+3, which belongs to IIIrd transition series (P < 0)

    (B) Due to higher oxidation state of Cobalt in3

    62

    III

    ])OH(Co[ , P < 0, also H2O lies towards

    stronger ligand side in spectrochemical series.

    (C) CO is a strong field ligand hence P <

    (D) Due to high value of Zeff

    of Pd2+ , which belongs to 2nd transition series , (P < ) ]

    [Only V-Group Batch]

    Q.12

    [Sol.

    N N

    + N=NNH

    NHN=N

    Me

    Me

    H O3+

    OH OH NH2

    NH2

    Me Me

    + + +H O3

    +

    ]

    [Only XY Batch]

    Q.13

    [Sol.

    NH2

    2HNO

    N N

    2N

    H

    ~H

    ringexp.

    H O2

    HO

    Possible products

    OH

    and

    HO

    ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    10/17

    CHEMISTRY

    Code-A Page # 5

    PART-C

    [Only V-Group Batch]

    Q.2

    [Sol. (a)

    Me Me

    CMe3 CMe3

    + E

    E

    (2)

    (b)

    NO2 NO2

    + E

    E

    (3)

    (c)

    NHCMe NHCMe

    O O

    + E

    E

    (4)

    (d)

    O O

    O O

    C CMe MeMe Me

    + E

    E

    (5) ]

    [Only XY Batch]

    Q.2

    [Sol. (a)

    O||

    CHCCH 33 +

    OD

    Me

    H CH CH2

    OHCross aldol

    O||

    CHCCH 23

    OD

    Me

    H CH

    C

    H+

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    11/17

    CHEMISTRY

    Code-A Page # 6

    Products:

    OCH

    |||CHCCHCCH

    |OH

    3

    323 (1) H

    D O

    Me

    CH2CHCH CCH2 3

    OH

    *(2)

    *CH

    C

    CH3

    CH3 CHO

    OH Me

    D

    H (2) H H

    D D

    Me Me

    CH2

    CH

    CH

    OH

    **

    CHO

    (4)

    Total 9

    (b) 8

    (c) Other than first all are diastereomers therefore 9

    (d) No enantiomers are formed therefore 0

    9890 ]

    Q.3

    [Sol. t1/2 = 30 minin 90 min, total 3 half lives

    Volume of H2O2 consumed = 28 + 2

    28+

    2

    14= 49 ml Ans. ]

    Q.4

    [Sol. C5H

    10O

    5

    ROH + CH CCl3

    O O

    ROCCH3

    MW1 + 43

    MW + 42

    C5H

    10O

    5MW = 150

    Remaining MW = 318150

    = 168

    4 42 4OH

    Structure

    CHO

    CH OH2

    OH

    OH

    OH

    H

    H

    H ]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    12/17

    MATHEMATICS

    Code-A Page # 1

    PART-A

    1. Using L Hospital's rule, we get

    L =4

    1

    x

    xsin4

    1

    0xLimit

    )xsin2(2

    xsinx

    0xLimit

    x2cos22

    xsinx

    0xLimit

    2

    ]

    2. The equation of plane containing A, B and C is

    212

    011 1z1y1x

    = 0

    A(1,1,1)

    M( , 2, 1)

    C(3,0,1)

    B(2,2,1)

    P(x,yz)

    2x + 2y3z + 3 = 0 ........(1)Clearly,M (, 2, 1) satisfy equation (1), so

    2 + 43 + 3 = 0 = 2. Ans.]

    3. Given x33x =c

    Let y = x33x and y =c

    Now,dx

    dy= 3x23

    1 1O

    y =

    c

    2

    2

    x

    y(1,2)

    (1, 2)

    x = 1 or1 (Graph of y = x33x is as shown)Clearly, for 3 distinct roots, we have

    c (2, 2) number of integers = {1, 0, 1} 3 Ans.

    4. For real roots D 0k24(k2 + 2k4) 0 3k28k + 16 0 3k2 + 8k16 0 3k2 + 12k4k16 0

    3k (k + 4)4(k + 4) 0 k

    3

    4,4 .

    Also, 2 + 2 = ( + )22= k22(k2 + 2k4) = k24k + 8 = 12 (k + 2)2Maximum value is 12 when k = 2. Ans.]

    5. 1c

    z

    b

    y

    a

    x2

    2

    2

    2

    2

    2

    .....(1)

    1c

    z

    b

    y

    a

    x2

    2

    2

    2

    2

    2

    ......(2)

    1c

    z

    b

    y

    a

    x2

    2

    2

    2

    2

    2

    .....(3)

    (1) + (2) + (3) 3c

    z

    b

    y

    a

    x2

    2

    2

    2

    2

    2

    .....(4)

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    13/17

    MATHEMATICS

    Code-A Page # 2

    From (1) and (4), 1c

    z2

    2

    z = c

    Hence, x = a, y = b, z = c.

    So, number of solution (x, y, z) = 2 2 2 = 8. Ans.

    6. I =

    6

    0dxxcos

    xsin1

    =

    6

    022 dx

    2

    xsin2

    xcos

    2

    xsin

    2

    xcos

    =

    6

    0

    2

    xsin

    2

    xcos

    dx

    =

    6

    0

    42xcos2

    dx

    =

    6

    0

    dx42

    xsec

    2

    1=

    6

    02

    x

    4tan

    2

    x

    4secn2

    l

    =

    12

    32n2 l = 3468n2 l . Ans.]

    Paragraph for question nos. 7 to 9

    Sol. We have

    L1

    :1

    4z

    1

    7y

    3

    6x

    = r

    1(say) ........(1)

    and L2

    :4

    2z

    2

    9y

    3

    x

    = r

    2(say) .......(2)

    Clearly, any point P on line L1

    is (3r1

    + 6, r1

    + 7, r1

    + 4) and any point Q on line L1

    is

    (3r2, 2r

    29, 4r

    2+ 2).

    So, direction ratios of PQ are 2rr4,16rr2,6r3r3 121212 .The points on the lines (1) and (2) which are nearest to each other will lie on line of shortest distance

    which will be perpendicular to both the given lines. If PQ is the line of shortest distance, then

    3(3r23r

    16)1(2r

    2+ r

    116) + 1(4r

    2r

    12) = 0

    i.e., 7r211r

    14 = 0 ........(3)

    and 3(3r23r

    16) + 2(2r

    2+ r

    116) + 4(4r

    2r

    12) = 0

    i.e., 29r2

    + 7r122 = 0 .......(4)

    On solving ((3) and (4) ,We get r

    1=1, r

    2= 1

    Point P(3, 8, 3) and Q(3,7, 6)

    7. The distance between P and Q = 222 368733 = 922536 = 303 .

    8. Equaton of plane OPQ, is

    673

    383

    0z0y0x

    = 0

    P(3,8,3) Q(3,7,6)

    O(0, 0, 0)

    P(x, y, z)

    23x9y + z = 0 Ans.

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    14/17

    MATHEMATICS

    Code-A Page # 3

    9. The value of parallelopiped formed by OQ,OP and OR where O is origin and R (1,1, 0)

    = |011

    673

    383

    ||OROQOP|

    = | 3(0 + 6)8(06) + 3(3 + 7) | = 304818 = 96. Ans.]

    10. We have

    (BTAB)T = BTAT (BT)T = BTATB = BTAB, iff A is symmetric.

    BTAB is symmetric iff A is symmetric.Also, (BTAB)T = BTATB = BTAB, iff A is skew-symmetric matrix. ]

    11.

    2 O(0,0)

    x=2x

    y

    9

    4,2A

    y=1

    +

    x=1

    B(2,4)

    +

    Graph of f(x) =3)1x(

    )4x( 3

    Now, verify alternatives. Ans.]

    12. Let the line be

    1b

    y

    a

    x , a, b > 0

    where 1b

    4

    a

    1

    a

    11

    b

    4

    a

    1a

    b

    4

    b =1a

    a4

    Now, 2A = ab = a

    1a

    a4

    = 1a

    )11a(4 2

    =

    1a

    1

    )1a(4

    da

    dA2 =

    2)1a(

    114 = 0

    B(0,8)

    A(2,0)Ox

    y

    a1 = 1 or1

    a = 2; b = 8, m =4

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    15/17

    MATHEMATICS

    Code-A Page # 4

    A]min

    =2

    16= 8

    Equation is (y4) = 4(x1) y4 = 4x + 4 4x + y = 8 Ans.

    Also, r =s

    =

    2

    6882

    822

    1

    =

    175

    8

    = 175

    Now verify alternatives. ]

    PART-B

    1.

    (A) Sn

    = 33.

    2

    n[2 + (n1) (n1)] = 33n (n1)2 = 64

    Hence n = 9. Ans.]

    (B) Domain of f(x) is x [1, 1]. Also f(x) is decreasing in its domain.

    At x =1 fmax

    (x =1) = cos1(1) + cot1(1) = +4

    3 =4

    7

    At x = 1 fmin.

    (x =1) = cos1(1) + cot1(1) = 0 +4

    =

    4

    4

    f(x)

    4

    7 0.8 f(x) 5.25 (approx.)

    (C) As 1 + sin 0,R so the given equation becomes cos = 1 + sin cos sin = 1.

    Clearly, = 0, 2,2

    3 . Ans.

    (D) D = 1 + 4a = (Odd No)2

    because of integral roots.

    let odd no = 2 + 1 then 1 + 4a = (2 + 1)2 = 42 + 4 + 1a = (+ 1) ; so a = 6, 12, 20, 30.Hence number of possible values of a are four. Ans.]

    PART-C

    1. Clearly, g'(x) = f(x) =

    2x1,x

    1x3,)2x(

    3

    2

    3

    g'(x) is a continuous function. ++1 0

    Sign scheme of g''(x)

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    16/17

    MATHEMATICS

    Code-A Page # 5

    g'(x) has a local maximum at x =1 and local minimum at x = 0.

    x=2x= 3 (2,0) x= 1 O(0,0)

    Graph of g'(x) = f(x)

    x

    y

    Hence, g'(x) has two extremum points. ]

    2. We have

    z2y0x4

    z0yx2

    z3y0x3

    =

    y34

    z1

    y28

    Now, on comparing we get system of equations as3x + 3z = 8 + 2y 3x2y + 3z = 8 ........(1)2x + y = 1 + z 2x + yz = 1 ........(2)4x + 2z = 4 + 3y 4x3y + 2z = 4 .........(3)

    On solving (1), (2) and (3), we getx = 1, y = 2, z = 3

    Hence, (x + y + z) = 1 + 2 + 3 = 6. Ans.]

    3. Given, f (x) = 2x3 + 3(13a)x2 + 6(a2a)x + b

    f ' (x) = 6[x2 + (13a)x + a(a1)] .......(1)As, f (x) has positive point of local maximum, so the equation f ' (x) = 0 must have both roots positive

    and distinct roots.

    D > 0 (13a)2 > 4a(a1) 16a + 9a2 > 4a24a 5a22a + 1 > 0, true a R. ......(2)

    Also, sum of roots > 0 (13a) > 0 3a > 1 a >3

    1......(3)

    and, product of roots > 0 a(a1) > 0 a < 0 or a > 1 .......(4)Hence, (2) (3) (4)

    a (1, )So, the smallest integral value of 'a' equals 2.]

  • 7/30/2019 Rt Solutions-18!12!2011 XIII VXY Paper I Code A

    17/17

    MATHEMATICS

    Code-A Page # 6

    4. Given, 7 sin 3x2 (3 sin 3x4 sin3 3x) = (1 + tan2) + 4 (1 + cot2)Put, sin 3x = y, we get

    y (8y2 + 1) = 9 + (tan 2 cot )2

    L.H.S. min occurs minimum value

    when y =1 and minimum value =9. = 9

    maximum occurs when y = 1 and maximum value = 9 when tan2= 2Hence maximum of L.H.S = minimum value of R.H.S.

    sin 3x = 1 = sin2

    x =

    6

    (minimum positive root).

    or sin 3x =

    2

    3sin x =

    2

    (maximum negative root).

    Sum =3

    2

    6

    3

    26

    .

    Hence,

    15 )rootnegative(maximumroot)positive(minimum =

    15

    3

    2= 10 Ans.]