Pcm 11th Paper -1 Code a (Jk&Pqrs) 02-01-2011

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    11th PQRS/JK (Date: 02-01-2011) Review Test-7/6

    Paper-1

    Code-A

    ANSWER KEY

    MATHS

    SECTION-3

    PART-A

    Q.1 D

    Q.2 B

    Q.3 C

    Q.4 BQ.5 D

    Q.6 A

    Q.7 B

    Q.8 C

    Q.9 A

    Q.10 A,D

    Q.11 C,D

    Q.12 A,C

    PART-B

    Q.1 (A) Q,

    (B) S,

    (C) T,

    (D) P

    PART-C

    Q.1 0001

    Q.2 0003

    Q.3 0084

    Q.4 0050

    Q.5 0008

    Q.6 5050

    PHYSICS

    SECTION-1

    PART-A

    Q.1 D

    Q.2 D

    Q.3 B

    Q.4 BQ.5 A

    Q.6 C

    Q.7 C

    Q.8 B

    Q.9 B

    Q.10 B,C,D or B,C

    Q.11 A,C,D

    Q.12 A,B,C

    PART-B

    Q.1 (A) P,S

    (B) Q,T

    (C) R,

    (D) R

    PART-C

    Q.1 0008

    Q.2 0002

    Q.3 0018

    Q.4 0066

    Q.5 0001

    Q.6 0026

    CHEMISTRY

    SECTION-2

    PART-A

    Q.1 B

    Q.2 D

    Q.3 C

    Q.4 C

    Q.5 B

    Q.6 C

    Q.7 C

    Q.8 B

    Q.9 A

    Q.10 C,D

    Q.11 A,B,C

    Q.12 B,C

    PART-B

    Q.1 (A)Q,R

    (B) P,Q

    (C) Q,R,T

    (D) P,S or P,Q,S

    PART-C

    Q.1 0007

    Q.2 0003

    Q.3 0004

    Q.4 0014

    Q.5 7642

    Q.6 2463

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    PHYSICS

    Code-A Page # 1

    PART-A

    Q.1

    [Sol.

    f1

    f2

    v

    ]

    Q.3

    [Sol. P is black so it will abosrb more energy faster. ]

    Q.4

    [Sol.F

    a

    f

    r F > f ]

    Q.5

    [Sol. (PE)max is same(KE)

    maxfor 1 > (KE)

    maxfor 2

    A1

    < A2

    1

    > 2

    Because KEmax

    =22Am

    2

    1 and m is same.]

    Q.6

    [Sol. For no toppling

    N = f= f

    2

    h

    ]

    Q.7

    [Sol. Adiabatic process

    B = P ]

    Q.8

    [Sol. Adiabatic process, 1

    TP= constant, so by differentiating with respect to y..

    dydT =

    PT

    1

    dydP ]

    Q.9

    [Sol. PV = nRT or P =M

    RT

    dy

    P=

    M

    Rdy

    dT]

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    PHYSICS

    Code-A Page # 2

    Q.10

    [Sol. a =2xx = A sin (t + ) phase

    KE =2

    1m2 (A2x2)

    PE =2

    1kx2 ]

    Q.11

    [Sol. (a) y is property of material

    (b) Breaking stres depends on material, force radius and length.

    (c) Strain depends on material, radius and force.

    (d) PE =2

    1(strain) (stress) (volume)

    So, it depends on force, material, radius and length. ]

    Q.12

    [Sol. (ML2

    T3

    ) = LX(ML3

    )y (ML2

    T2

    )1 = y + z 2 = x3y2z3 =2z or z = 3/2

    and y =1/2 x = 7/2P (linear size)7/2 (density of air)1/2 (g density of helicopter)3/2 ]

    PART-B

    Q.1

    [Sol. (i) m >M, (ii) m

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    PHYSICS

    Code-A Page # 3

    Alternative :

    A1

    A2 t = 0

    12cm

    12cm

    6cm

    = t

    t = t

    t = 0/36

    12

    =3

    t =3

    t =6

    T= 2 sec. ]

    Q.3

    [Sol. mgh =2

    1mv2 +

    2

    1I2

    20m

    13m

    h = 7m

    v

    H

    =2

    1m(2g (H13)) +

    2

    1

    5

    2m(r22)

    g(7) = g(H13) +5

    1(v2)

    = g(H

    13) +51 (2g(H

    13))

    7 = (H13) +5

    2(H13)

    7 =5

    7(H13)

    H = 18 m ]

    Q.4

    [Sol. T' = T

    ag

    u2

    = 2

    g

    ag

    =g

    g (1 + ) = (g + a)Reading = m (g + a) = mg(1 + ) = (60) (10) (1 + 20 104 50) = 600 (1 + 0.1) = 660 NewtonApparent weight = 66 kg ]

    Q.5

    [Sol. = ma

    2

    sin

    m(a)

    (pseudo force)

    a =

    3

    m

    sin2

    ma

    2

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    PHYSICS

    Code-A Page # 4

    =2

    a3sin

    for slightly open is very smallsin

    =

    2

    a3

    2

    2

    dt

    d = (2)

    = 0 cos (t)

    time taken to shut =4

    T=

    4

    /2 =

    2

    a32

    = a6

    distance travelled by car = 0 +2

    1at2 =

    2

    1a p2

    a6

    =

    12

    2

    =12

    )2.1)(10(= 1 m ]

    Q.6

    [Sol. 3kx1

    + kx2

    = ma

    3k k

    m

    xx

    x2

    xx 21

    6kx1

    = ma

    m

    kx3= a

    a =3

    6763= 26 ]

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    CHEMISTRY

    Code-A Page # 1

    PART-A

    Q.1

    [Sol. N 1s2 2s2 2p3

    O 1s2 2s2 2p4

    Half filled configurationmore stable, required more energy to remove the electron as compare to

    O-atom ]

    Q.2

    [Sol.

    1

    2

    3

    5

    4

    6

    7

    8

    6-ethyl-2, 2, 3, 7-tetramethyl octane. ]

    Q.3

    [Sol. 98 gram 80 gram

    H2SO

    4+ 2NaOH Na

    2SO

    4+ 2H

    2O

    H3PO4 + NaOH Na2HPO4 + H2O98 gram 40 gram

    40 gram NaOH reacts with 49 gram H2SO

    4& 98 gram H

    3PO

    4to form sulphate & dihydrogen

    phosphate.

    wt. ratio

    H2SO

    4: H

    3PO

    4

    49 98

    1 :2 Ans. ]

    Q.4

    [Sol. N

    H

    it is not homocyclic since hetero atom is present within the ring. ]

    Q.5

    [Sol. H O2

    H2

    T1

    = T

    P1

    = 830

    30 = 800 mm

    P1

    = 2

    T2

    = 0.9 T

    2

    2

    1

    1

    T

    P

    T

    P or

    T9.0

    P

    T

    800 2

    P2

    = 720 mm

    Ptotal

    at 2nd temp. = 720 + 45 = 745 mm Ans. ]

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    CHEMISTRY

    Code-A Page # 2

    Q.6

    [Sol.Vem2

    h

    8

    Ve2'm2

    h

    8

    Ve2'm = m e V

    m' = 4m ]

    Q.7

    [Sol.V

    150

    V = 24 volt Energy of free electron = 24 eV,

    E = 13.6 (Z)2

    1612

    = 1.51 eV

    total energy released = 24(1.51) = 25.51 ]

    Q.8

    [Sol. (n2)

    62 = 4 ]

    Q.9

    [Sol. Min. energy transition for 6

    5 ]

    Q.10

    [Sol. SiF2Cl

    2 sp3 not sp3d ]

    Q.11

    [Sol. Molecular formulaC4H

    6

    D. B. E. 2

    Possibility 2bond

    or 1 bond & 1 ring

    or 2 ring ]

    PART-B

    Q.1[Sol. (D) Assuming only translational kinetic energy Ans. P,S

    Assuming translational, rotational as well as vibrational K.E. Ans. P,Q,S ]

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    CHEMISTRY

    Code-A Page # 3

    PART-C

    Q.1

    [Sol. CH3Cl sp3 tetrahedral

    C

    H

    H H

    Cl

    One according toabove structure

    6along the faces

    Total = 6 + 1 = 7 ]

    Q.2

    [Sol. wsol.

    = 1140

    wB

    = 210

    wA

    + wsolvent

    = 930

    10nA

    + OH2

    n18 = 930

    19nA

    + OH2

    n = 7

    342nA

    OH2n18 = 126 352 n

    A= 1056 ; n

    A= 3 ]

    Q.3

    [Sol Zr+3 [Ar] 5s0 4d1

    1s2

    2s2

    3s2

    2p6

    3p6

    4p6

    3d10

    4d1

    5s0

    4s2 LHS to the 4d all electrons

    contributes one

    Z = Z

    = 40 36 1 = 4

    1

    eff

    ]

    Q.4

    [Sol. Total number of SS bond = (n1)

    n : total number of S-atom

    S15O62

    S = 15SS bonds are 151 = 14 ]

    Q.5

    [Sol. ]

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    CHEMISTRY

    Code-A Page # 4

    Q.6

    [Sol. PGL PVm

    = RT

    Vm

    =11

    K300

    P

    RT

    VG

    = R3011

    K3001.1 = 30 0.0821

    VG 2.463 lit. = 2463 Ans. ]

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    MATHEMATICS

    Code-A Page # 1

    PART-A

    Q.1

    [Sol. Clearly, min.(2x2ax + 2) and max. (b 1 + 2x x2) will occur at the vertices of the parabolas

    y = 2x2ax + 2 and y = b1 + 2xx2 respectively, so that min. (2x2ax + 2) = 28

    a2

    and

    max. (b1 + 2xx2) = b

    Hence, 2

    8

    a2

    > b 16a2 > 8b a

    2 + 8b

    16 < 0 a2

    4 (4

    2b) < 0.

    Now, discriminant of 2x2 + ax + (2b) = 0, is a24 (42b), which is less than zero.

    Hence, all roots of the equation 2x2 + ax + 2b = 0 are imaginary. Ans.]

    Q.2

    [Sol. Let required line be, (y0) = m (x6), m > 0

    mxy6m = 0 .....(1)As distance of above line from N(1, 3) is 5, so

    2m1

    m63m

    = 5 (3 + 5m)2 = 25(1+m2) 9 + 30m = 25 m =

    30

    16=

    15

    8. Ans.]

    Q.3

    [Sol. Case-I: ;!2!3!7

    !10

    Case-II: 0 0 1 1 1 1 1 1 2 2 ; !2!2!2!2!6

    !10

    Hence total =

    !2!2!2!2!6

    !10

    !2!3!7

    !10!10 = 31560!10 = 375 10! k = 375 Ans.]

    Q.4

    [Sol. We have 12

    zz

    2

    zz

    | x | + | y | = 1

    Also, |zi| + |z + i| = 2

    A line segment between

    (0, 1) and (0,

    1).So, number of solution is 2

    i.e., z = i and i ]

    Q.5

    [Sol. Clearly, equation of required circle, is(x + 1)2 + (y1)2 + (x + y) = 0

    x2 + y2 + ( + 2)x + (2)y + 2 = 0 ..........(1)As circle (1) intersects the circle x2 + y2 + 6x4y + 18 = 0 orthogonally,

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    MATHEMATICS

    Code-A Page # 2

    so using orthogonality condition, we get

    2

    2

    223

    2

    2= 18 + 2

    (3 + 6)(24) = 20 = 10So, putting = 10 in equation, we get

    x2 + y2 + 12x + 8y + 2 = 0.

    Clearly, radius = 246 22 = 21636 = 50 = 25 Ans.]Q.6

    [Sol. We have

    Q =

    n

    0r1r

    r

    )3cos(

    )3sin(=

    3cos

    sin+

    9cos

    3sin+

    27cos

    9sin+ ............... +

    )3cos(

    )3sin(1n

    n

    As,

    3cos

    sin=

    3coscos2

    cossin2=

    3coscos2

    2sin

    =21

    3coscos

    3sin =21 (tan 3tan )

    Q =2

    1[(tan 3tan ) + (tan 9tan 3) + ........... + (tan 3n + 1tan3n)]

    Q =2

    P P = 2Q. Ans.]

    [PARAGRAPH TYPE]

    Q.7 to Q.9 has four choices (A), (B), (C), (D) out of which ONLY ONE is correct.

    Paragraph for question no. 7 to 9

    [Sol. Given C: x22x cos + cos 2 + cos +2

    1

    (i) x =a2

    b=

    2

    cos2 = cos

    As vertex lies on y = x

    cos = cos22cos2 + (2cos21) + cos +2

    1

    0 = cos221 cos2 =

    21 =

    47,

    45,

    43,

    4 4 values Ans.

    (ii) If C touches l then discriminant = 0

    x2(2cos + 1)x + 2cos2 + cos 2

    1= 0 has equal roots

    So, (2cos + 1)2 = 4

    2

    1coscos2 2

    4cos2 + 4cos + 1 = 8cos2 + 4cos 2

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    MATHEMATICS

    Code-A Page # 3

    4cos2 = 3 cos2 =4

    3

    =6

    11,

    6

    7,

    6

    5,

    6

    sum =

    6

    24= 4Ans.

    (iii) If y = x intersects at A (x1, x

    1) and B (x

    2, x

    2) (x , x )

    1 1

    A

    y=

    xB(x , x )

    2 2

    X

    Y

    O (0, 0)

    l

    C

    (AB)2 = 2 (x1x

    2)2

    = 2[(x1

    + x2)24x

    1x

    2] .......(1)

    Solving, we get

    x22x cos + cos 2 + cos +2

    1= x

    (2cos + 1)x + 2cos2 + cos 2

    1= 0

    Now, sum of roots = x1

    + x2

    = 2cos + 1

    Product of roots = x1x

    2= 2cos2 + cos

    2

    1

    Hence (AB)2 = 2

    2

    1coscos241cos2 22

    = 2[4cos2 + 1 + 4cos 8cos24cos + 2] = 2 [34cos2] = 68cos2

    So, AB is max. if =2

    or

    2

    3(i.e., cos2 = 0)

    (AB)max.

    = 6 = L

    Hence, 6 = 2 Ans.]

    Q.10

    [Sol. We have

    2xcos

    1xcos

    2

    2

    , 1 + tan22y 1, 2 3 + sin 3z 4

    So, the only possibility is cos2x +xcos

    12 = 2, 1 + tan

    22y = 1, 3 + sin 3z = 2.

    cosx = 1 x = n, n I

    Also, tan 2y = 0 y =2

    m, m I and sin 3z =1 z = (4k1)

    2

    , k I. Ans.]

    Q.11

    [Sol. We have

    x1

    + x2

    + ........ + x100

    =2

    100(x

    1+ x

    100) = 1 ............(1)

    and x2

    + x4

    + ....... + x100

    =2

    50(x

    1+ d + x

    100) = 1 ............(2)

    Solving (1) and (2), we get

    d =50

    3

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    MATHEMATICS

    Code-A Page # 4

    So, x1

    =50

    149

    Also, x100

    =25

    74

    Now, sum of infinite G.P. =

    50

    31

    25

    47

    =

    47

    94= 2. Ans.]

    Q.12

    [Sol. Let the slope of tangent at B be m and it makes 45 with 3x5y = 1, so tan 45 =

    5

    m31

    5

    3m

    m = 4,

    4

    1. Ans.]

    PART-B

    Q.1

    [Sol.

    (A) C6

    can be seated any where in the row. For C5

    there are two options one just before C6

    and one just

    after C6. similarly for C

    4also there are 2 options Total 25 = 32 Ans.

    (B)

    !31C3

    6

    places3select

    6C4 2! = 12030 = 90 Ans.

    Alternatively : 6C4 3 2! = 15 3 2 = 90 Ans.

    (C) Give one to each of the 6 children. Now 4 remaining can be given as follows:

    (i) 1 marble to each of 4 children 6C4= 15 ways

    (ii) 2 marbles to each of two children 6C2= 15

    (iii) 3 marbles to one and 1 to other of five = 6C1

    5C1

    = 30

    (iv) 1 marbles to two and 2 marbles to 1 child 6C2 4C

    1= 60

    So, total ways = 120 Ans.

    (D) Select 3 out of six in 6C3ways for one column and 3 rejected children on the other column can be

    arranged only in 1 way

    Hence number of ways 6C3 1 = 20 ways Ans.]

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    MATHEMATICS

    Code-A Page # 5

    PART-C

    Q.1

    [Sol. Chord of contact with mid-points (h, k) is hx + ky = h2 + k2 ...(1) Also chord of contact

    of (x1, y

    1) is xx

    1+ yy

    1= 2 ...(2)

    On comparing (1) & (2), we get

    x1

    =22 kh

    h2

    , y

    1=

    22 kh

    k2

    As (x1, y1) lies on 3x + 4y = 10 6h + 8k = 10(h2

    + k2

    ),

    x2 + y2 y5

    4x

    5

    3 = 0, which is a circle with centre P

    10

    4,

    10

    3

    Clearly, distance of M

    10

    2,

    10

    11from P

    10

    4,

    10

    3

    =

    10

    2

    10

    4

    10

    3

    10

    112

    =100

    36

    100

    64 = 1. Ans.]

    Q.2

    [Sol. Let cos = t, so we get 2t16logtlogt4

    2

    2

    2

    t

    4log

    t16logtlog

    2

    22

    2

    2

    tlog2

    tlog4tlog

    2

    22

    2

    Let log2

    t = z, so z2 +

    z2

    z4= 2 z(z22z3) = 0 z = 0,1, 3.

    t = 1,21 , 8,

    So, cos = 1 or cos =2

    1 = 2n

    3

    or = 2m, n, m I.

    Hence, number of solutions are 3

    0,

    3

    5,

    3,e.i . Ans.]

    Q.3

    [Sol. Let a2

    = x2

    + 6, a3

    = x3

    + 2, a4

    = x4

    + 1.

    So, a1 + a2 + a3 + a4 = 15 a1 + x2 + x3 + x4 = 9, where a1, x2, x3, x4 0So, using begger's method, we get number of solutions = 9C

    3= 84. Ans.]

    Q.4

    [Sol. If a, x, y, z, b are in A.P., then b = 5th term = a + 4d (d = common difference)

    d =4

    ab

    xyz = (a + d) (a + 2d) (a + 3d) = 55 (given)

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    MATHEMATICS

    Code-A Page # 6

    4

    b3a

    4

    b2a2

    4

    a3b= 55

    (a + 3b) (a + b) (3a + b) = 55 32 .......(1)Again, if a, x, y, z, b are in H.P., then common difference of the associated A.P. is

    a

    1

    b

    1

    4

    1

    i.e.,

    ab4

    ba

    x

    1

    =

    ab4

    ba

    a

    1

    x = b3a

    ab4

    y

    1=

    ab4

    ba2

    a

    1 y =

    b2a2

    ab4

    =

    ba

    ab2

    andz

    1=

    ab4

    ba3

    a

    1 z =

    ba3

    ab4

    so, xyz =

    ba3

    ab4

    ba

    ab2

    b3a

    ab4=

    55

    343(given)

    3255ba32

    33

    =

    55

    343 a3 b3 = 343 ab = 7 a = 7, b = 1 or a = 1, b = 7

    So, sum = (a2 + b2) = 50 Ans.]

    Q.5

    [Sol. AM = MB

    Now, APB = 90

    AM = PM = MB = 22 )2k()1h( P(1,2)

    C(3,4)B

    M(h,k)

    A

    90

    In CMB, CB2 = CM2 + MB2

    36 = (h3)2 + (k4)2 + (h1)2 + (k2)2

    36 = 2h2 + 2k2

    8h

    12k + 30 Locus of (h, k) is

    x2 + y24x6y3 = 0

    So, (a + b + c) = 2 + 3 + 3 = 8. Ans.]

    Q.6

    [Sol. We have 11x2x2

    Case I: If x 2

    1 | 2x(2x1)| = 1, which is true given equation is satisfied x

    2

    1.

    Case-II : If x < 2

    1

    )1x2(x2 = 1 | 4x1| = 1 4x1 = 1 x = 0, 2

    1

    x = 0.

    2

    1xReject

    So, solution set is x {0}

    ,

    2

    1.

    Hence, sum = 1 + 2 + .......... + 100 =2

    101100= 50 101 = 5050. Ans.]