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    GENER L INSTRUCTIONS

    1. In addition to this question paper, you are given a separate answer sheet.

    2. Fill up all the entries carefully in the space provided on the OMR sheet ONLY IN BLOCK CAPITALS.

    Incomplete/incorrect/carelessly filled information may disqualify your candidature.

    3. A student has to write his/her answers in the OMR sheet by darkening the appropriate bubble with the

    help of HB Pencil as the correct answer(s) of the question attempted.

    4. Paper carries 80 questions each of 3 marks.

    5. Any rough work should be done only on the blank space provided at the end of question paper.

    6. Foreach correct answer gets 3 marks, each wrong answer gets a penalty of 1 mark.

    7. Blank papers, clip boards, log tables, slide rule, calculators, mobiles or any other electronic gadgets in

    any form is "NOT PERMISSIBLE".

    Time : 2 Hr. Date : 27-Oct-2014) Max. Marks : 240

    PCCP OFFICE

    :Address :C-8, Lakshya, Nursery Plots, Talwandi, Kota (Rajasthan)-324005

    Tel No : +91-0744-3022244 3022245 Fax : 022-39167222 | Website : www pccp resonance ac in

    ALL INDIA IJSO(STAGE-I) TEST SERIES

    MOCK TEST PAPER # 8

    http://www.pccp.resonance.ac.in/
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    9. In a quadrilateral ABCD, +B = 90 and, AD2= AB2 + BC2+ CD2, then +ACD is equal to,

    (A) 90 (B) 60 (C) 30 (D) None of these

    10. If the roots of the equation 3ax2+ 2bx + c = 0 are in the ratio 2 : 3 then,

    (A) 8ac = 25 b (B) 8ac = 9b2 (C) 8b2 = 9ac (D) 8b2 = 25ac

    11. If (5,3) , (4,2) and (1,

    2) are the midpoints of sides of a triangle ABC, then the area of ,ABC is,(A) 2 sq. units (B) 3 sq. units (C) 1 sq. units (D) 4 sq. units

    12. A rectangular sheet of metal x cm by y cm has a square of size zcm cut from each corner. The sheet is

    then bent to form a tray of depth z cm. The volume of the tray is :

    (A) z (x + z) (y z) (B) xyz (C) z(x 2z) (y2z) (D) (x + y) z

    13. If a5x = b5y = c5z and a2 = bc, then what is the value of xy + xz 2yz :

    (A) 0 (B) 1 (C) 5 (D) 25

    14. In the figure given below, AB is a diameter of the semicircle APQB with centre O, +POQ = 48 cuts BPat X, calculate +AXP.

    OA B

    QPX

    48

    (A) 50 (B) 55 (C) 66 (D) 40

    15. If x + y + z = 0, then find the value of! "! "! "

    xyz

    xzzyyx ###

    (A) 6 (B) 2 (C) 4 (D) 1

    16. Find the number of two digit numbers divisible by the product of the digits.

    (A) 7 (B) 11 (C) 4 (D) 5

    17. Ifba

    c

    ac

    b

    cb

    a

    #-

    #-

    #, then each fraction is equal to :

    (A) 2

    1(B) 1 (C) 2 (D) 2

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    18. If a, b, c are in A.P., thenba

    1

    #,

    ca

    1

    #,

    cb

    1

    #are in :

    (A) A.P. (B) G.P. (C) H.P. (D) None of these

    19. The angles of elevation of the top of a vertical tower from points at distances a & b from the base and in

    the same line with it are complementary. If a > b then the height of the tower is -

    (A)ab .

    (B)a

    b(C)

    ab #(D)

    ba

    20. In the diagram if ,ABC and ,PQR are equilateral. The +CXY equals :

    (A) 35 (B) 40 (C) 45 (D) 50

    21. Find equivalent Resistance across A and B :

    R

    R

    R

    R

    B

    RR

    A

    (A)2

    R3(B) R (C) 2R (D)

    2

    R

    22. Each of the three graphs represents acceleration vs time for an object that has a positive velocity at time

    t1which graphshows that speed is increasing for the time interval between t

    1and t

    2?

    a

    t1 t2

    a

    t1 t2

    a

    t1 t2(A) graph Ionly (B) graph Iand IIonly (C) graph Iand III only (D) graph I, II and III

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    23. A shell is fired from a gun at an angle to the horizontal.Which set of graph shows correctly its horizontal

    component of velocity vxand its vertical component of volocity V

    y.

    (A)

    t

    vx

    t

    vy

    (B)

    t

    vx

    t

    vy

    (C)

    t

    vx

    t

    vy

    (D)

    t

    vy

    t

    vx

    Direction for Q. No. 24-25: The circuit shown in figure contains two batteries. For shown circuit answer

    the following questions.

    16v

    B1

    A B

    CDB2

    8v

    In the circuit shown above

    24. What is the potential difference across 5/Resistor is

    (A)17

    40V, with A at higher potential (B)

    17

    40V, with D at higher potential

    (C)2

    5V, with A at higher potential (D)

    2

    5V, with D at higher potential

    25. For above figure find the correct statement :

    (A) Battery B1is getting charged and B

    2is getting discharged

    (B) Battery B1, is getting discharged and B

    2is getting charged

    (C) Both batteries are getting charged

    (D) Both batteries are getting discharged

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    26. A stone of mass mis thrown with an initial velocity u making angle 1with Horizontal surface it strikes

    with a smooth Horizontal surface. The duration of impact is ,T then calculate the normal force applied by

    surface to the stone [cellision is perfectly elastic].

    n

    U

    (A)T

    mu2

    ,(B)

    T

    sinmu2

    ,1

    (C)T

    cosmu2

    ,1

    (D)T

    sinmu

    ,1

    27. In given figure, a ball mA= 5kg is moving on smooth horizontal surface with a velocity 2m/s it collides with

    bob of mass mB= 5kg and comes to rest. Collision is perfectly elastic find calculate minimum height to

    which bob lift.[take g = 10 m/s2]

    B

    h

    A 2m/s

    (A) 10m (B) 50m (C) 0.2m (D) data is insufficient

    28. In above question, find the work done by tension force of the string on the bob during its motion.

    (A) 50 J (B) 10 J (C) Zero (D) Can not calculate

    29. When mgram of water at 10C is mixed with mgram of ice at 0C which of the following statement is/

    are true ?

    (A) The temperature of the system at steady state will be given by the equation

    m 80 + m 1 (T

    0) = m 1 (10

    T)(B) Whole ice will melt and temperature will be more than 0C but lesser than 10C

    (C) Whole of ice will melt and temperature will be 0C

    (D) Whole of ice will not melt and temperature will be 0C

    30. A ball whose density is 0.4 103kg/m3fall into water from height of 9cm To what depth does the ball sink

    (A) 10cm (B) 9cm (C) 6cm (D) 1cm

    31. A 10 gm bullet is moving in a straight line with a speed 500 m/s penetrates a 1kg block which is also

    moving in the same line with1ms1 , on a frictionless surface. Right after being penetrated by the bullet , the

    block moves with 2 ms1.What is the velocity of the bullet right after it emerges from the block ?

    (A) 100 m/s (B) 200 m/s (C) 300 m/s (D) 400 m/s

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    32. It is known that when one uses a single battery in connection with a light bulb, the battery can last for

    time t.If one tries to use two Identical batteries in connection with two Identical light bulbs, which one of

    the following statement is correct ?

    (A) If the batteries are in parallel and the light bulbs are in series, then batteries can give power for time t/2

    (B) If the batteries are in series and the light bulbs are in series, then batteries can give power for 2t

    (C) If the batteries are in parallel and the light bulbs are in parallel then batteris can power for t

    (D) If the batteries are in series and the light bulbs are in parallel .Then batteries can power for 4t

    33. It is known that when 0.1 kg of metal A at 52C is placed in 0.3 kg of some liquid B at 10C the final

    temperature is 16C Assuming that all of the relavant heat capacities do not depend on temperature and

    there is no heat lost. What is the final temperature when 2kg of metal A at 60C is placed in 0.5 kg of

    liquid B at 12C.

    (A) 42C (B) 36C (C) 28C (D) 44

    34. A loop PQRS is formed by joining two semi circular wires of is Radii R1and R

    2carries a current I as

    shown. The magnitude of magnetic induction at centre C is

    o R 1

    R2

    (A)4023

    $$%

    &''(

    )

    12

    1

    R

    1

    R

    R(B)

    4023 $$

    %

    &''(

    )

    21 R

    1

    R

    1(C) 3oI $$

    %

    &''(

    )

    12 R

    1

    R

    1(D) 3oI $$

    %

    &''(

    )

    1R

    1

    35. When a charged particle moves in a megnetic field, it is K.E. always :

    (A) Increases

    (B) decreases

    (C) remain constant(D) increases or decreases depends on direction of projectile

    36. A lens is made up of two different material such that two images are formed as shown . Then which of the

    following may provide a correct explanation.

    I2 I1O

    (A) 31=3

    2(B) 3

    1> 3

    2(C) 3

    1< 3

    2(D) Data Insufficient

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    37. Match the column

    Column-I Column-II

    (1) (P) Ferromagnetic

    (2) (q) Paramagnetic

    (3) (r) Diamagnetic

    (A) (1) q ; (3) r ; (2) P (B) (1) p ; (2) q , (3) r

    (C) (1)r ; (2) q (3) p (D) None

    38.

    4 4 1

    10V

    2 2

    1

    Find current drawn from battery(A) 6A (B) 2A (C) 10A (D) 5A

    39. A simple pendulum of length !has time period Tit dipped completely in water assume resistance

    offered by water moleculs is zero then time period of pendulum will.

    (A) Increases (B) decreases (C) Remain same (D) data is insafficient

    40. A thin steel pin sinks in sea water but a huge ship does not sink why ?

    (A) Because area of pin is small

    (B) Because area of ship is very large

    (C) Because miximum part of ship is hollow filled with air so average density decreases from water

    (D) None of these

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    41. Which of the following state of a given element is incorrect :

    (A) O2

    (B) O3

    (C) B12

    (D) P2

    42. Which of the following statement is incorrect :-

    (A) Ne-gas is used in artificial respiration with O2.

    (B) Chlorine is both germicide and bleaching agent.

    (C) Tannic acid is used as a mordant in dyeing industry.

    (D) In a coloured compound, colour is produced by both cation and anion.

    43. For a given carbon - skeleton.

    Which of the following is identical

    (a) (B) (C) (D) both (a) and (b) are correct

    44. If elements have atomic no. 11, 12 and 16 then nature of their oxides will be respectively.

    (A) Acidic, Acidic and Basic (B) Basic, Acidic and Acidic

    (C) Basic, Basic and Acidic (D) None of these

    45. A hydrocarbon has 3 g carbon per g of hydrogen hence simplest formula is : -

    (A) CH4

    (B) C6H

    6(C) C

    3H

    8(D) CH

    2

    46. Select the correct lewis structure of given species :-

    (A) OC = N

    (B) C2

    C (C) (D) N =O

    47. Correct order of energy of given rays is : -(A) *-ray > 4 -ray > 5-ray(B) *-ray > 5.ray > 4-ray(C) 5-ray >* -ray > 4-ray(D) None of these

    48. a As2O

    3+ b MnO

    4 + c H+ + H

    2O67H

    3AsO

    4+ Mn2+. In the given reaction, coefficient a,b and c

    respectively are : -

    (A) 4, 5 and 7 (B) 6, 3 and 7 (C) 5, 6 and 7 (D) 5, 4 and 12

    49. An aqueous solution of 6.3 g oxalic acid dihydrate is made upto 250 ml. The volume of 0.1N NaOH

    required to completely neutralise 10 ml of this solution is : -(A) 40 ml (B) 20 ml (C) 10 ml (D) 30 ml

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    50. When lead nitrate is heated up, gases formed is/are :

    (A) NO and O2

    (B) N2O and O

    2(C) NO

    2and O

    2(D) N

    2O and NO

    2

    51. Which of the following is the readymade source of hydrogen :(A) Ionic hydride (B) Metallic hydride (C) Ammonia (D) both (A) and (B)

    52. Select incorrect statement :(A) H+ exist as H

    9O

    4+in water

    (B) H2 is thermally stable(C) Ionisation of CH3COOH is slower than that of CH

    3COOD.

    (D) When H2O is replaced by D

    2O, then rate of reaction is retard.

    53. Which of the following is correct for hydrogen peroxide (H2O

    2) -

    (A) It act as both oxidising as well as reducing agent.(B) It is used as a fuel for rockets.(C) It is used as an antiseptic in surgery.(D) All are correct.

    54. Which of the following structure is correct for a molecular formula C6H

    4O

    2?

    (A) COOH (B) OO (C) OO (D)

    O

    O

    55. CaCO3is decomposed by HCl (d = 1.825 g/cc)

    CaCO3+2HCl67CaCl

    2+ H

    2O + CO

    2

    Volume of HCl required to decompose 10g of 50% pure CaCO3is :-

    (A) 1.825 ml (B) 3.65 ml (C) 0.9125 ml (D) 2 ml

    56. Amongst H2O , H

    2S , H

    2Se and H

    2Te, the one with highest boiling point is : -

    (A) H2O because of hydrogen bonding.

    (B) H2Te because of higher molecular weight

    (C) H2S because of hydrogen bonding.

    (D) H2Se because of lower molecular weight.

    57. Which is not the correct process-mineral matching in metallurgical extraction ?(A) Leaching - Ag (B) Zone refining - Sn(C) Liquation - Sn (D) Van arkel - Zr

    58. A flow diagram is given below related to metallurgical process :-

    This flow diagram is related to which process for extraction of alumina :-

    (A) Baeyers process (B) Serpeks process (C) Halls process (D) Krolls process

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    59. Which of the following is known as corrosive sublimate ?(A) HgCl

    2(B) Hg

    2Cl

    2(C) HgSO

    4(D) Hg

    2I

    2

    60. The reaction 3ClO(aq.)

    67ClO3 + 2Clis an example of :-

    (A) Oxidation reaction (B) Reduction reaction(C) Disproportionation reaction (D) Combination reaction

    61. An exergonic biochemical reaction in which a organic molecule convert into an organic acid. It shouldtake place in :-

    (A) Mitochondrial Matrix (B) Cytoplasm(C) PeriMitochondrial sapce (D) Chromatophore

    62. Physiologically which one is odd :-(A) Pepsin (B) Trypsin (C) Chymotrypsin (D) Trypsinogen

    63. Kupffers cells present in liver :-(A) Synthesise Bile salts (B) Synthesis Aqueous part(C) Stores Vitamin D (D) None of these

    64. Which one is uricotelic : -(A) Land invertebrate (B) Land reptiles (C) Bony fishes (D) Mammals

    65. Which group of aminoacids is essential in infants :

    (A) Arginine & histidine (B) Leucine & histidine(C) Arginine & Lysine (D)Leucine & Lysine

    66. The pollination in plants by Homo-Sapiens will be referred as :-(A) Zoophily (B) Entomophily (C) Artificial type (D) Malacophily

    67. Progesterone level in female human get reduced during:-(A) Proliferative phase (B) Ovulatory phase (C) Secretory phase (D) Menstrual phase

    68. Which one enters into reductional cell division .(A) Primary spermatocyte (B) Secondary spermatocyte(C) Spermatogonium (D) Spermatids

    69. When a Red flowered plant crossed with white flowered plant of same species, Pink flowered progeny

    produced this incident is not following :-(A) Principle of dominance (B) First law of Mendel(C) Principle of Independence (D) Both (A) and (B) are right

    70. Blood group of a child is O.His Parents May have blood of the group randomly :-(A) only O (B) B or O (C) A and AB (D) Only AB

    71. During reflex action Brain is involved as : -(A) Reflex - action centre (B) Brain is not involved(C) Learning centre after reflex action (D) Hyperactive centre during reflex - action

    72. Which of the cell can not be used to solve cases of Paternal inheritance :-(A) Monocytes (B) Lymphocytes (C) Basophils (D) Erythrocytes

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    73. In which of the following ATP consumption occur :-(A) glycolysis (B) Krebs cycle(C) Oxidative decarboxylation (D) None of these

    74. A Plant is growing at the stage in which lenticels are not formed . Possibly which of the chemical presentin lesser amount at this stage : -(A) Pectin (B) Starch (C) Suberin (D) Cellulose

    75. What is glycosuria :

    (A) Conversion of glucose into urea (B) Urea attached or bind with glucose(C) Appearance of glucose in urine (D) isotonic solution of glucose and urea.

    76. An organism having choanocytes is a multicellular entity. Organisation level of this organism will be : -(A) Cellular level (B) Tissue level (C) Organ level (D) Organ system level

    77. Which one is not an organ : -(A) Tentacles of Hydra (B) Sucker of Leech (C) Skin of earth worm (D) tube feet in starfish

    78. A plant is exposed to 310 nm wavelength spectra the pothosynthetic rate will : -(A) increased (B) decreased(C) ceased (D) First decreased then increased

    79. In DNA , the association of nitrogenous bases AGCT occur as per which of the following pair :

    (A) A = T, G 8 C (B) A = G, C 8T (C) A 8C, G = T (D) None of these

    80. Bryophytes are characterized by :(A) Multicellular jacketed archegonia(B) Thalloid body(C) Dominant gametophyte and partial parasitic saprophytic(D) All above

    Maths : 1 to 20Phy : 21 to 40Che. : 41 to 60Bio : 61 to 80

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    SOL._IJSO STAGE-I _MOCK TEST-1_PAGE # 1

    NSWER KEY

    HINTS & SOLUTIONS

    ALL INDIA IJSO (STAGE-I)

    TEST SERIES

    MOCK TEST-1(28-10-12)

    1. a = ! "323# , b = ! "323

    $ab = ! "323# ! " 323

    Now, (a + 1)1+ (b + 1)1=1b)(1a(

    1a1b

    ##

    ###

    =1baab

    2ba

    #####

    =2ba

    2ba

    ####

    = 1

    Hence option (C).

    2. Let five consecutive even numbers are, 2n, 2n+2,

    2n+4, 2n+6, 2n+8 where n%n.

    and , five consective and numbers will be 2n +

    1, 2n + 3, 2n + 5, 2n + 7, 2n + 9

    $N ]

    =2n 2n 2 2n 4 2n 6 2n 8

    2n 1 2n 3 2n 5 2n 7 2n 9

    # # # # # # # #

    # # # # # # # # #

    =5.2n

    2n

    25n10

    20n10

    ##

    #

    Hence option (D)

    3. a2

    a1'

    # ) a2a1 '#

    Similarly b2b1 '# , c2c1 '# & d2d1 '#

    $(1 + a) (1 + b) (1 + c) (1 + d) abcd16'

    * +1abcd16 &' !

    Que s. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

    Ans. C D C A B B B B A D A C A C D D A A D B

    Que s. 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

    Ans. D D A A B B C C D C B C D B C C B D A C

    Que s. 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

    Ans. D C D C A C D D A C A C D C D A B B A C

    Que s. 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80

    Ans. B A D B A C D A A B C D A C C A A C A D

    4. Volume of water in conical flask = ha3

    1 2,

    Volume of water in cylidrical flask = Hp2,

    Both volumes are equal

    So, ha3

    1 2, = Hp2,

    $ 22

    p3

    haH& cm

    5. ax= by= cz= dw= k (let)

    )xlogaa = ylog

    ab = zlog

    ac = wlog

    ad = log

    a\k

    Now, loga(bcd) = log

    ab + log

    ac + log

    ad

    =y

    1logk +

    z

    1logk +

    w

    1logk

    = logk --

    .

    /00

    1

    2##

    w

    1

    z

    1

    y

    1

    = x --.

    /001

    2##

    w

    1

    z

    1

    y

    1Ans. (B)

    6. Ar (cX) = 4 Ar(cY)

    ),x2= 4,(r)2

    )x2= (2r)2= x = 2r

    $AB = 22 r4r # = 2r5 = 5 r

    Ans. (B)

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    SOL._IJSO STAGE-I _MOCK TEST-1_PAGE # 2

    7. n(U) = 15, n(G) = 7, n(F) = 8 and )'F'G(n 3 = 3

    )'F'G(n 3 = 3

    n(GUF) = 3

    n(U) n(GUF) = 3

    n(GUF) = 15 3 = 12

    Now, n(GUF) = n(G) + n(F) )HG(n 3

    12 = 7 + 8 )HG(n 3

    15 12 = )HG(n 3

    )HG(n 3 = 3

    So, 3 have studied both german & French.

    8. sin 4+ cosec 4= 2Now (sin 4+ cosec 4)2= 22

    ) sin2x + cosec2x = 222 = 2) (sin2x + cosec2x) (sin x + cosec x) = 4) sin3x + cosec3x + sin2x cosecx + sin2xcosecx = 4) sin3x + cosec3x + sinx cosecx (sinx + cosecx)

    = 4) (sin3x + cosec3x) + 2 = 4) sin3x + cosec3x = 2) (sin2x + cosec2x)2= 22

    ) sin4 x + cosec4x + 2 = 22

    ) sin4 x + cosec4x = 2similarly, sinnx + cosecnx = 2.

    9.

    A B

    C

    D

    In 5ABC,AC2= AB2+ BC2

    Given : AD2 = AB2 + BC2+ CD2

    AD2 CD2 = AB2 + BC2

    So, AC2= AD2 CD2

    AC2+ CD2 = AD2

    So, by converse of pythagoras theorem6ACD = 90.

    10. Equation : 3ax2+ 2bx + c = 0

    Its roots are 24& 34

    so, 54=a3

    b2and 642=

    a3

    c

    Eliminating 4we get, 8b2= 25ac.

    Ans. (D)

    11.

    B

    A

    CD

    F E(4, 2)

    (5, 3)

    (1,2)

    We know that Area of 5ABC = 4 Area of 5DEF

    Area of 5DEF =

    )23(1)32(4)22(52

    17#77##

    = 120202

    1#7 =

    2

    1sq. units

    So, area of 5ABC = 4 area of 5DEF

    = 4 2

    1= 2 sq. unit

    12.

    A B

    CD

    x

    y

    z

    Length of tray = x 2z

    Breadth of tray = y 2z

    Height of tray = z

    So, volume of tray = z(x 2z) (y2z)

    13. Let, a5x = b5y = c5z = k

    a = x51

    k , b = y51

    k and z = z51

    k

    a2 = bc

    z5

    1y5

    1

    x5

    2

    kkk 8&

    z5

    1

    y5

    1

    x5

    2

    kk#

    &

    So,z5

    1

    y5

    1

    x5

    2#& or

    z

    1

    y

    1

    x

    2#&

    2yz = xz + xy

    xy + xz 2yz = 0

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    SOL._IJSO STAGE-I _MOCK TEST-1_PAGE # 3

    14. 6POQ = 48.

    OA B

    QPX

    48

    6PBQ = 24

    [Angle subtended at the centre is double thanthe angle subtended by it on the remain part of

    the circle]

    6PAQ = 6PBQ = 24 [Angle in the samesegment of a circle are equal]

    In 5PAX6APX = 90 [ Angle in a semi circle is a 90]

    So, 6AXP = 180 90 24 = 66

    15.! "! "! "

    xyz

    xzzyyx ###

    x + y = z, y + z = x, z + x = y[!x + y + z = 0]

    So,! "! "! "

    xyz

    yxz 777=

    ! "xyz

    xyz7= 1.

    16. There are 5 two digits numbers i.e. 11, 12, 15,

    24, 36 which is divisible by the product of the

    digits.

    17.ba

    c

    ac

    b

    cb

    a

    #&

    #&

    #= k

    a = k(b + c), b = k(c + a), c = k (a+b)

    Add all

    a + b + c = 2k (a + b + c)

    k =2

    1

    18. If a, b, c are in A.P.

    Then, b a = c b

    " "abab 7# = " "bcbc 7#Divide by ! "! "! "accbba ###

    ! "! "! "! "! "accbba

    abab

    ###

    7#

    =

    ! "! "! "! "! "accbba

    bcbc

    ###

    7#

    ! "! "! "accb

    ab

    ##

    7=

    ! "! "! "acba

    bc

    ##

    7

    cb

    1

    ac

    1

    #7

    #=

    ac

    1

    ba

    1

    #7

    #

    So,cb

    1

    ba

    1

    ac

    2

    ##

    #&

    #

    $ba

    1

    #,

    ca

    1

    #,

    cb

    1

    #are in A.P..

    19. Let OT be the tower of height h.

    Let O be the base of the tower.

    Let A and B be two points on the line through

    the base such that OA = a and OB = b.

    In 5AOT,

    tan 4= OA

    OT

    = a

    h

    ...(i)

    B b OA

    T

    a

    h

    In 5BOT

    tan (90 4) =OB

    OT=

    b

    h

    ) cot 4=b

    h....(ii)

    Multiplying (i) and (ii) , we have

    tan4cot 4=b

    h

    a

    h8

    ) tan 44tan

    1=

    ab

    h2

    ) 1 =ab

    h2

    ) h2= ab

    ) h = ab .

    Height of tower = ab .

    20.

    5ABC & 5PQR are both equilateral triangle.In 5PQR,6RPQ = 60So, 6RPB = 180 60 75 = 45Similarly, 6CBP = 180 60 65 = 55So, in 5BPY6BYP = 180 55 45 = 80$In 5CXY6CYX =6BYP = 80 [Vertically oppositeangles]

    So, 6CXY = 180 80 60 = 40.

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    SOL._IJSO STAGE-I _MOCK TEST-1_PAGE # 4

    21.

    R

    R

    R

    B B

    R

    A

    R

    C D

    R

    A

    [ VC

    = VD]

    A

    B

    R2R

    2

    R2R

    22. (D) in all casses a"

    is in positive direction.

    23. (A) V = ucos ,Vyx

    = usin gt

    both will form straight line

    24. (A) 16 1.6 I 5I1.4 I 8 9 I= 0

    =I=17

    8A

    = VAV

    D=

    17

    8 5 =

    17

    40V

    25. (B) Current withdrawn from battery B, and goes

    into Battery B2.

    26. (B) PInitial

    = mv Sin 9j (in y-axis)

    [before collision]

    PFinal

    = mv sin9j

    [after collision]

    F =t

    P

    55

    =T

    jsinmv2

    59

    27. (C) Apply conservaion of linear momentum and

    conservation of mechanical energy.

    28. (C) T is : to distance

    29. (D) Sind m 80 > m (100)

    30. (C)

    V=0f(B)

    V1

    9cm

    (A)

    x

    V1= gh2

    Mg

    Fb

    a

    V1= 2109102 7888

    V1= 8.1 m/s

    retardation =gv

    gvvg

    bb

    bb

    ;;7;

    vb= v

    a =b

    b )(g

    ;;7;

    a =400

    )4001000(10 7= 15 m/s2

    after x displacement

    vf= 0

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