STPM Trial 2009 Phy Q&A (Melaka)

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  • 8/14/2019 STPM Trial 2009 Phy Q&A (Melaka)

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    PERSIDANGAN KEBANGSAAN PENGETUA-PENGETUASEKOLAH MENENGAH MALAYSIA

    CAWANGAN MELAKA

    JANGAN BUKA KERTAS SOALAN INI SEHINGGA ANDA DIBENARKAN

    BERBUAT DEMIKIAN.

    AdaLIMA puluh soalan dalam kertas ini. Bagi setiap soalan, empat cadangan jawapan

    diberikan. Pilih satu jawapan yang betul dan tandakan jawapan itu pada helaian jawapan aneka.

    Pilihan yang diberikan..

    Baca arahan pada Kertas Jawapan aneka pilihan itu dengan teliti.

    Jawap semuasoalan. Markah tidak akan ditolak bagi jawapan yang salah.

    Gunakan buku/helaian data sendiri..

    * This question paper is CONFIDENTIAL until the examination is over.

    * Kertas soalan ini SULIT sehingga peperiksaan kertas ini tamat.[Turn over/Lihat sebelahCONFIDENTIAL*/SULIT*

    This question paper consists of 19 printed pages and 1 blank page.

    Kertas soalan ini terdiri daripada 19 halaman bercetak 1 halaman kosong.

    DO NOT OPEN THE BOOKLET UNTIL YOU ARE TOLD TO DO SO.

    There are fifty questions in this paper. For each question, four suggested answers are given.

    Choose one correct answer and indicate it on the multiple-choice answer sheet provided.

    Read the instruction on the multiple-choice answer sheet very carefully.

    Answerall questions. Marks will not be deducted for wrong answers.

    Use your own data book/sheet

    Arahan kepada calon:

    PENILAIAN PENGESANAN PEPERIKSAAN

    SIJIL TINGGI PERSEKOLAHAN MALAYSIA 2009

    Instructions to candidates

    STPM TRIAL 960/1

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    PERSIDANGANKEBANGSAANPENGETUAPENGETUAPERSIDANGANKEBANGSAAN

    960/1 STPM TRIAL 2009

    PHYSICS (FIZIK)

    PAPER 1 ( KERTAS 1)

    MULTIPLE-CHOICE (ANEKA PILIHAN)

    One hour and forty-five minutes (Satu jam empat puluh lima minit)

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    1. A student measured in the length, width and height of a cubical wooden block, using a ruler with

    accuracy of 0.05 cm. He then calculated the volume of the block, and his calculator registered108.288. Which of the following alternatives would be the best one to express his results, withoutlosing accuracy and without including meaningless figure?

    A. 108.29 cm3

    B. 108.3 cm3

    C. 110 cm3

    D. 108 cm3

    2. What is the dimension of thermal conductivity?

    A. MLT-3

    B. ML-3-1 C. MLT

    -3-1 D. ML-3T-1

    3. A projectile of mass m is fired with velocity v from a point P, as shown below.

    Neglecting air resistance, the magnitude of the change in momentum between leaving P and

    arriving at Q is

    A. mv B. mv 3 C. 2 mv D. mv 2

    600

    P Q

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    4. A body is moving with constant speed in the y-direction. For positive values ofy, it experiences auniform acceleration in the x- direction. Which one of the paths A to D does it follow?

    5. A ball hits the ground normally with a speed u. Which of the following is NOT TRUE if the

    collision is elastic?

    A. The particle rebounds along its original path with speed u.B. The momentum of the ball is conserved.

    C. The kinetic energy of the ball is conserved.

    D. The total momentum of the ball and the floor is conserved.

    y

    x

    y

    y

    y

    x

    x

    x

    x

    A.

    B.

    C.

    D.

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    6. An 5.0 kg block slides down a rough plane which is inclined at 30 as shown below.

    The box starts from rest and then moves a distance of 2.0 m as measured along the incline.

    After it has moved this distance, its speed equals 2.0 m s-1

    . What is the coefficient of kinetic

    friction between the block and the plane?

    A. 0.46 B. 0.80 C. 1.04 D. 1.15

    7. Two forces P and Q of the same magnitude act on a uniform metre rule pivoted at O as shown

    below.

    Which of the following statements is TRUE?

    A. The resultant forces P and Q on the metre rule is zero.

    B. Both forces P and Q exert an anti- clockwise moment about O.

    C. The moment of force P about O is greater than that of force Q about O

    D. The system is in static equilibrium.8.

    F

    A force is applied to a regular cubical block of weight 10 N as shown above. What is the leastmagnitude of F required to overturn the block?

    A. 2 N B. 5 N C. 10 N D. 20 N

    O

    P

    Q

    40cm

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    9. The diagram below shows a cyclist making a left turn on a rough road surface at constant

    speed v, as viewed from behind. The total mass of the bicycle and rider is m and their

    combined center of gravity is at G.

    IfR is the resultant force of the normal reaction and the frictional force, which vector

    diagram represents the directions of forces acting on the bicycle and its rider in an

    inertial frame?

    10. A planet of mass mmoves in a circular orbit of radiusR round a sun of massMwith period T.Which one of the following correctly shows how Tdepends on m,R and M?

    A.22

    3

    mRT C 21

    2

    3

    MRT

    B. 21

    2

    3

    MRT D 21

    2

    3

    mRT

    A C

    BD

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    11. A body is released from rest at a point P a distance 3R from the centre of an isolated planet

    with radius R and mass M. What is the speed of the body on hitting the planet?

    A.R

    GM

    3

    2B.

    R

    GM

    3C.

    R

    GM

    3

    4D.

    R

    GM2

    12. The given diagram shows two identical bodies, represented by P, Q moving in simple

    harmonic motions.

    If the springs are identical, the ratio ofPofnoscillatioofPeriod

    QofnoscillatioofPeriodis

    A. 0.5 B. 0.707 C 1.41 D. 2

    13. . A small mass executes s.h.m. about a point O with amplitude a and period T. Its

    displacement from O at time8

    Tafter passing through O is

    A.2

    aB.

    22

    aC.

    2

    aD.

    8

    a

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    14. The diagram below shows the Searle's apparatus often used in determining the Youngs

    Modulus of a metal. Which of the following statements NOT TRUE about the experiment ?

    A. Two wires of the same material and length are hung side by side from the same clamp.

    B. Long and thin wire should be used so as to produce a greater extension.

    C. Vernier scale is used so as to measure the extension more accurately.D. The error due to thermal expansion of the wire is not taken into consideration.

    15. The graph below shows how the force Fbetween two atoms in a solid varies with the

    distance rbetween them. Which of the following statements about the distance a and b

    marked on the graph is CORRECT?

    A. The potential energy is a minimum at b.

    B. When r< b, the force is repulsive.

    C. The stiffness of the solid depends on the slope of the curve near a.

    D. Area under the graph for r > b is equal to the bonding energy.

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    16. A vessel of volume 1x10-3

    m contains 0.72 g of an ideal gas of O2 at a pressure of 1x105

    Pa. The r.m.s. velocity of the gas molecules is

    A 20 m s-1

    B 110 m s-1

    C 340 m s-1

    D 650 m s-1

    17. Which of the following is NOT an assumption in deriving the kinetic theory of gases?

    A Attractive forces between the molecules are negligible.

    B The volume of the molecules is negligible compared with the volume of the gas.

    C The duration of a collision is negligible compared with the time between collisions.

    D The molecules experience negligible change of momentum on collision with the walls

    of the container

    18. The energy which must be supplied to 1 mole of gas initially at absolute temperature T,

    pressurep and volume V, to increase its temperature by 1K, is Q1at constant pressure and Q2at

    constant volume. The value of Q2is

    A Q1

    B Q1 + pVT

    C Q1 - pVT

    DT

    pVQ

    1

    19. The graph below shows the distribution of molecular speed at room temperature.

    As the temperature is increased,

    A the peak position will move to the right and its height will increase

    B the peak position will move to the right and its height will decrease

    C the peak position will move to the left and its height will increase

    D the peak position will move to the left and its height will decrease

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    20. An ideal gas undergoes a cyclic process involving two isothermal changes and two

    adiabatic changes as shown in the diagram below.

    Which of statements below is TRUE about the changes?

    A Heat is supplied to the gas and there is net work done by the gas without any increase

    in internal energy.

    B There is net heat supplied to the gas causing its internal energy to increase.

    C The net work done by the gas causes the internal energy to increase, but the net heat

    flow is zero

    D There is net work done on the gas causing heat to be released by the gas without any

    change in internal energy.

    21. A glass window pane is 1.4 m high, 1.1 m wide and 3 mm thick. The temperature at the

    inner surface of the glass is 22C and at the outer surface 4C. How much heat is lost each

    hour through the window? (Thermal conductivity of glass = 0.812 W m-1

    K-1

    )

    A. 2.7 107 JB.

    2.7 10

    4

    J

    C. 7.4 103 JD. 7.4 J

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    22. The diagram below shows a conducting sphere of radius a carries an excessive charge

    of + Q. An uncharged metal rod MN is brought near the sphere. The axis of the rod is

    collinear with a diameter through a point L on the sphere.

    Which of the following graphs best illustrates the variation of potential V with

    distance x along their common axes?

    A. C

    B. D

    23. An electron travels at speed of 1.0 x 106

    m s-1

    along the direction of the field lines in

    a uniform electric field. Its speed is reduced to zero at a distance of 4.0 x 10-2

    m. What is

    the strength of the electric field?

    A. 0.71 V m-1

    C. 71 V m-1

    B. 22x103

    V m-1

    D. 22x109

    V m-1

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    24. A 100 F capacitor is discharged through a resistor of resistance R. The graph below shows

    the variation of voltage V across the capacitor against timet.

    According to the graph, what is the approximate value of R?

    A. 20 K B 35 K C 50 K D 200 K

    25. The diagram below shows three resistors of resistances 4 , 10 and 6 connected

    in series. A potential difference of 10 V is maintained across them, with point Q

    being earthed.

    Which graphs represents the change in electric potential along the resistor

    network?

    4 10 6QP R S

    10V

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    A C

    B D

    26. The diagram below shows a cylindrical metal wire of cross-sectional area A contains n

    conduction electrons per cubic meter. When a potential difference is applied across the

    ends P and Q of the wire, electrons will drift from P to Q with a mean velocity v.

    Consider the electrons in the shaded volume of length x m, which of the

    following statements is NOT TRUE?

    A. The number of electrons in the shaded volume isnAx.B. All electrons in the shaded volume will pass through the cross-section at R in

    timex / v.

    C. The rate at which the conduction electrons pass through thecross- section at R isnv.

    D. The current flowing in the metal wire is given byneAv

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    27. The diagram represents an aircraft of length l, wingspanx, flying horizontally at speed v in a

    region where the Earths magnetic field, of uniform flux densityB, is inclined at an angle to the Earths surface.

    Which expression gives the magnitude of the e.m.f. generated between the wingtips by

    electromagnetic induction?

    A. B l v sin

    B. B l x

    C. B x v

    D. B x v sin

    28. . When a coil is rotated in a magnetic field, the induced e.m.f.E varies with time as shown

    in the graph below.

    Which of the following graphs, drawn to the same scale, would be obtained if the speed

    of rotation of the coil were doubled?

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    30. The figure below shows a thin horizontal copper plate where current I flows along the

    direction OS in a vertical magnetic field.

    I P

    Q

    Copper plate O R

    S

    B

    The Hall voltage which exists in the copper plate will produce an electric field acting along

    the direction

    A OP B OQ C OR D OS

    31. A potential difference Vis applied across a wire of length l and resistivity. If the wire has nfree electrons per unit volume, the drift velocity of the free electrons in the wire is

    A Vlne

    B nel

    V

    C neV

    L

    D lne

    V

    32. In an ideal transformer, the most important function of the soft-iron core is

    A. to produce a uniform radial magnetic field in the two coils.

    B. to reduce the back e.m.f. produced in the coils.

    C. to increase the current in the coils.

    D. to improve the flux-linkage between the two coils.

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    33. An a.c. supply is connected to a resistor. When the peak value of the e.m.f. of the supply is

    Vo and the frequency is f , the mean power dissipated in the resistor is P . The supply

    frequency is then changed to 3f, the peak value of the e.m.f. remains unchanged.

    What is now the mean power in the resistor?

    A. P B. 3 P C. 3P D. 6P

    34. The diagram below shows an operational amplifier.

    What is the gain of the amplifier?

    A.4 B. 5 C. 6 D. 20

    35. The displacementy of a point in a progressive wave with time tis given by

    ty 4sin15.0=

    The wave has wavelength of 5.0 m. Determine the speed of the wave.

    A 2.5 m s-1

    B 10 m s-1

    C 63 m s-1

    D 79 m s-1

    -

    +50Vi Vo

    1000

    200

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    36 The graph below illustrates a transverse pulse at a certain instant which is moving towards

    the left along a stretched string.

    What is the direction of motion of point P at this instant?

    A Positive-x direction

    B Negative-x directionC Positive-y direction

    D Negative-y direction

    37 A point source of sound produces sound of power 500 W. What is the intensity level of

    sound at 5.0 m away? (Threshold intensity of hearing = 1.00x10-12

    W m-2

    )

    A 122 dB B 128 dB C 132 dB D 140 dB

    38 The frequencies of a tuning fork and a note of a piano are f1 andf2 respectively. When bothfrequencies are played, beats are heard. If now a little plasticine is attached to the tuning

    fork, it vibrates with frequencyf3. It produces beats of higher frequency with the same piano

    note. Which relation between the frequencies is TRUE?

    Af3 >f1

    Bf1>f2

    Cf1

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    41 Which electromagnetic wave has frequency in the order of 1.0 x 1016

    Hz?

    A Radio wave B microwave C visible light D ultraviolet

    42 The lens of a sunglasses is made up of lamination of two polarisers with its axis of

    polarisation making an angle of 30o

    . What is the percentage of the intensity of the incident

    light transmitted?

    A 37 % B 43% C 57% D 63 %

    43 Two loudspeakers separated by a short distance produces sound of the same frequency. At a

    position in front of the speakers, the path difference from the position to each of the speakers

    is 1.2 m. At that position, maximum loudness is heard when the frequency is 1000 Hz andthe next maximum is heard when the frequency is increased to 1200 Hz. What is the speed

    of sound based on the observation?

    A 120 m s-1

    B 240 m s-1

    C 300 m s-1

    D 340 m s-1

    44 A converging lens of focal length 12.0 cm forms an upright image three times the size of the

    object. The distance between the object and the image is

    A 16.0 cm B 32.0 cm C 48.0 cm D 64.0 cm

    45 The diagram below show the air wedge formed by inserting a thin piece of paper at the edge

    of two slide glasses.

    When monochromatic light is incident normally from above, interference pattern is

    observed. The fringe separation becomes narrower when

    A thinner paper is used

    B the paper is pulled further to the edge

    C monochromatic light of longer wavelength is used

    D the air wedge is replaced with water to form the water wedge

    46 Sodium lamps emit light strongly at two very closely wavelengths. There are the sodium-D

    lines at 589.0 nm and 589.6 nm. If a diffracting grating with 500 lines per mm is used,

    calculate the angular separation between the first order spectra lines due to these

    wavelengths?

    A 0.017o B 0.018

    o C 17.13

    o D 17.15

    o

    Paper

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    47. A photocathode whose work function is 2.7 eV is illuminated with white light that has a

    continuous wavelength band from 400 nm to 700 nm. The range of the wavelength band inthis white light illumination for which photoelectrons are not produced is

    A. 460 nm to 700 nm

    B. 400 nm to 520 nm

    C. 460 nm to 520 nm

    D. 520 nm to 700 nm

    48. Characteristic x-rays can be produced by bombarding targets with electrons. These x-rays

    occur when

    A electrons from higher shells fill the vacant lower shell

    B electrons fill the vacant valence shell

    C electrons decelerate and radiate energy

    D electrons transfer all their kinetic energy to the target atoms.

    49. For stable nuclei with large mass number, the ratio of protons to neutrons isA equal to 1B. greater than 1C less than 1

    D. unrelated to the stability of nuclei

    50. Find the binding energy of carbon-12.

    Assume:mC = 11.996706 u

    mp

    = 1.007276 u

    mn

    = 1.008665 u

    u = 1.66 1027

    A 0.511 MeV

    kg

    B. 9.11 MeVC. 14.8 MeVD. 92.3 MeV

    ------------------------------------------------END--------------------------------------------------------------

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    CONFIDENTIAL* 1

    960/2

    *This question paper is CONFIDENTIAL until the examination is over. CONFIDENTIAL*

    This question paper consists of 13 printed pages and 1 blank page.

    (Kertas soalan ini terdiri daripada 13 halaman bercetak dan 1 halaman kosong.)

    960/2

    * This question paper is CONFIDENTIAL until the examination is over.

    *Kertas soalan ini SULIT sehingga peperiksaan kertas ini tamat.

    [Turn over (Lihat sebelah)CONFIDENTIAL*

    SULIT*

    Identity card number:.....

    (Nombor kad pengenalan)

    Instruction to candidates:

    DO NOT OPEN THE BOOKLET UNTIL YOU ARE TOLD

    TO DO SO.

    Answer all the que stions i n s ection A i n t he s paces pr ovided. A llworkingmust be shown. For calculation, relevant values of constants in

    the data book let must be us ed. F or numerical answers, uni t must bequoted whenever they are appropriate.

    Answer any four questions from section B. For this section, write youranswers on t he ans wer sheets pr ovided. Begin each answer on a f resh

    sheet of paper, and arrange your answers in numerical order.Tie your answer sheets to this booklet.

    Answer may be written in either English or Malay.

    Arahan kepada calon:

    JANGAN BUKA KERTAS SOALAN INI SEHINGGA ANDA

    DIBENARKAN BERBUAT DEMIKIAN.

    Jawab semua soalan dalam b ahagian A da lam r uang y ang d isediakan..Semua k erja mestilah ditunjukkan. Bagi pe nghitungan nilai p emalar y ang

    berkaitan dalam Buku Data mestilah digunakan. Bagi jawapan berangka, unitmestilah dinyatakandi mana-mana yang sesuai.

    Jawap mana-mana empat soalan. dalam bahagian B. Untukbahagian ini, tulis jawapan andapada helaian yang dibekalkan. . Mulakan

    setiap j awapan pada h elaian k ertas y ang ba ru, dan s usun jawapan andamengikut t ertib be rangka. I kat k ertas j awapan and a be rsama de ngan k ertas

    soalan ini.Jawapan boleh ditulis dalam bahasa Inggeris atau bahasa Melayu.

    CONFIDENTIAL*/SULIT*

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUAPERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    960/2 STPM TRIAL 2009

    PHYSICS (FIZIK)

    PAPER 2 ( KERTAS 2)

    STRUCTURE AND ESSAY (STRUKTUR DAN ESEI)

    Two and a half hours (Dua jam setengah)

    For examiners use

    (Untuk kegunaan

    pemeriksa)

    1

    2

    3

    4

    5

    6

    7

    8

    9

    10

    11

    12

    13

    14

    Total

    (Jumlah)

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    CONFIDENTIAL* 2

    960/2

    *This question paper is CONFIDENTIAL until the examination is over. CONFIDENTIAL*

    Section A [ 40 marks ]

    Answerallthe questions in this section.

    1. (a) Explain what is meant by work and power. [2]

    (b) A car of mass 1540 kg is moving up a slope making an angle of 30o

    with the horizontal.

    The total air resistance acting on the car is 500N. If the car is moving at a constant

    speed of 20.0 m s-1

    ,

    (i) calculate the force exert by the engine. [2]

    (ii) find the power of the engine.

    [2]

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    2. A uniform beam having a mass of 60 kg and a length of 2.8 m is held in place at itslower end by a pin. Its upper end leans against a vertical frictionless wall as shown inthe figure.

    (a) In the diagram below, show the direction of reaction forces acting on thebeam and the weight of the beam. [3]

    (b) What is the magnitude of the force the pin exerts on the beam? [3]

    40o

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    3. a) Based on a thermodynamic law, explain the drop in the temperature of a gas

    during an adiabatic expansion. [2]

    (b) The following p-V graph represents a cyclic process in an ideal gas of constant mass.

    The overall process is represented by three separate changes I, II and III.

    i) Identify which change represents adiabatic change? [1]

    ii) If the above processes represents the changes in a heat engine, in what sequencemust the three processes take place? Explain how you deduce your answer. [2]

    P

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    4. (a) A sound source of a certain frequency moving towards a stationary observer. The

    frequency of the sound heard by the observer is different from that of the source.

    Explain this phenomenon in terms of change in wavelength, frequency and velocity.

    [3 ]

    (b) A car traveling normally towards a cliff at a speed of 30 m s-1

    sounds its horn which

    emits a note of frequency 100 Hz. What is the frequency of the echo as heard by the

    driver? (Speed of sound is 330 m s-1

    . ) [3]

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    5. (a) A parallel-plate capacitor of capacitance Cand a resistor of large resistanceR are

    connected in series with a battery of e.m.f.Ehaving negligible internal resistance.

    (i) Sketch graphs to show the time variation of the voltage across the capacitor and the

    current in the circuit after closing switch S. [2]

    (ii) With switch Sclosed, the plates of the capacitor are pulled apart slightly. Describe and

    explain the possible change(s) in the charge and the energy stored in the capacitor

    when the steady state is reached. [3]

    E

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    6. You are given some isotopes of a certain element. The isotopes are ionized so that they can

    carry the same charge Q, and enter a speed selector as shown in the diagram below. Onlythose isotopes with a definite speed can pass straight through the mutually perpendicular

    uniform electric and magnetic fields in the speed selector. The whole set-up is in a

    vacuum environment.

    (i) Explain how the speed selector works. [2]

    (ii) Describe and explain how the isotopes can be distinguished experimentally by

    directing the emerging beam of ionized isotopes into a uniform magnetic field.

    [3]

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    7. The diagram below shows two point charges,A andB, separated by a distance of 1.20 m

    QA = 1.50 10-6

    C and QB= +4.20 10-6

    C

    (a) Calculate the magnitude and direction of electric field at pointP, midway between the

    charges. [3]

    (b) Calculate the electric potential at pointP. [2]

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    8. In an X-ray tube, electrons are accelerated towards an anode by a potential differenceof 10,500 V.

    (a)Calculate the de Broglie wavelength of the electrons just before collision withthe anode. [3]

    (b) Calculate the minimum wavelength in the X-ray continuous spectrum. [2]

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    Section B [ 60 marks ]

    Answer anyfour questions in this section.

    9. (a) State Newtons Law of Universal Gravitation. [1]

    (b) A satellite of mass 200 kg is placed in a circular orbit at a height of 200 km above the

    Earths equator travelling in the same direction as the rotation of Earth about its own

    axis.

    (i) Explain why the centre of the orbit must be at the centre of the Earth. [2]

    (ii) Calculate the speed of the satellite. [3]

    (iii) The satellite passes a particular place on the ground at certain time of the day, by

    taking into account the rotation of the Earth, find the time interval it will pass the

    same place again ? [4]

    (iv) By ignoring air resistance, calculate the minimum energy required to launch the

    satellite into its orbit from the ground. [3]

    (v) What is the minimum speed of the satellite in the orbit so that it can escape from the

    gravitational field of the Earth and travel to infinity. [2]

    (Radius of Earth R = 6.40x106

    m)

    10. a) The pressurep of an ideal gas of density is related to the mean-square speed of

    its molecules by the expression

    i) State three basic assumptions of the kinetic theory of gases, which lead to a model

    of an ideal gas [3]

    ii) Write down the equation for an ideal gas. Explain the symbols you use.

    [2]

    iii) Show that the average kinetic energy of a molecule of an ideal gas is proportional

    to the thermodynamic temperature T. [4]

    b) A tank contains 2.0 moles of helium gas at 200C. The molar mass of helium is 4.0 g.

    Assume that the helium gas behaves as an ideal gas

    i) find the total internal energy of the system [2]

    ii) what is the average kinetic energy per molecule [2]

    iii) determine the r.m.s. speed of the helium atoms at 200C. [2]

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    11. (a) State the phenomenon which proved that light is a transverse wave? [1 mark](b) The diagram below shows a charge oscillating along they-axis.

    The oscillating charge produces an EM wave propagating in the positive-z direction.

    State the respective axis in which the oscillations of the electric field component E andthe magnetic field component B of the wave. [2 ]

    (c) The light from a light bulb is a unpolarized light. Explain. [2 ]

    (d) The polarizing material consists of parallel long straight chain molecules. When

    unpolarized light passing through it, the light transmitted will be polarized light.

    (i) State the direction of the polarizing axis referring to the long straight chain

    molecules. [1 ]

    (ii) Explain what happens when an EM wave passes through these long straight

    chain molecules. [2 ]

    (iii) If the electric field component of the EM wave is lost, what happens to the

    magnetic field component? [1 ]

    (e) The diagram below shows an unpolarized light of intensityIo passing through two

    polarizers.

    (i) State the intensity of light after passing through the first polarizer in terms ofIo and

    explain your answer [3 ]

    (ii) Calculate the angle if the light emitted from the two polarizers has intensity 25%that of the incident light. [3 ]

    x

    z

    Charge

    y

    Polarizing axis

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    12. (a) Explain what is meant by mutual inductance between two coils. [1]

    (b) A large long solenoid is made with 60 turns per centimeter. A smaller solenoid has

    30 turns, is 2.0 cm long and has a diameter of 0.80 cm. The ends of the small

    solenoid are connected to a 10 resistor. The small solenoid is placed right inthe centre of the large solenoid. In the diagram below the small solenoid is

    shown outside the large solenoid for clarity. The large solenoid is then connected

    to a DC power supply which changes the current in the large solenoid from zero to

    10 A in a time of 2.0 ms.

    I

    Power Supply

    i) Calculate the magnitude of the magnetic field in the large solenoid when the currentis at its maximum value of 10 A. [2]

    ii) Calculate the average current passing through the 10 resistor while the current in

    the large solenoid is changing. [3]

    iii) If the direction of the current in the large solenoid is as shown in the diagram, in

    which direction does current go in the resistor (to the left or to the right)?

    [1]

    iv) Calculate the mutual inductance of the two coils. [3]

    (c) An AC motor of an electric drill has a resistance of 13.0 . When it is turning at its

    maximum speed it draws an rms current of 2.10 A when connected to a 120 V rms

    supply.

    i) Calculate the back emf when the drill is running at its maximum speed. [2]

    ii) Calculate the rms current drawn by the drill when it is drilling through somehardwood at one quarter of its maximum speed. [3]

    10

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    13 (a) State the difference between X-rays and-rays. [2]

    (b) (i) Sketch a graph to show the variation of the intensity with wavelength for the X-

    ray spectra obtain at two different voltages V1 and V2 (V1 < V2 ) from an X-ray tube.

    [2]

    (ii) Explain how the continuous spectrum and the characteristic line spectrum of X-

    rays are formed. [4]

    (c) The K series of the discrete X-ray spectrum of tungsten contains wavelengths of 0.0209

    nm (transition from L to K shell) , and 0.0215 nm (transition from M to K shell). The

    K-shell ionization energy is 69.5 keV.

    (i) Draw a diagram of the transitions. [2]

    (ii) Determine the ionization energies of the L and M shell. [5]

    14. (a)Potassium-40 is a radioactive isotope of potassium which is present in human body.The main decay mode is for K40

    19to decay by the emission of a beta particle to produce

    the stable product of Ca4020 .

    Write an equation for this radioactive decay process. [1]

    (b) Calculate the energy emitted in Joule when one nucleus of K4019

    undergoes the above

    decay process. Explain why the mass of beta particle is not considered in your

    calculation. [5]

    (c) 0.3% of the human body mass is potassium of which only 0.0117% of the potassium

    are isotope K4019 . Calculate the number of isotope K4019 atoms per kilogram of the

    human body. [2]

    (d) If the half life of K4019 is 1.28x109

    years, calculate the rate of decay of K4019 in Bq per

    kilogram in the human body. [4]

    (e) One third of the energy of each decay is deposited in the body. Calculate the total

    energy absorbed by a boy of mass 40 kg in one year. [3]

    Given : The mass of one K40

    19 atom = 39.964000 u

    The mass of one Ca4020

    atom = 39.962591 u

    -----------------------------------------END--------------------------------------------------------------

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    This question paper consists of 13 printed pages and 1 blank page.

    (Kertas soalan ini terdiri daripada 13 halaman bercetak dan 1 halaman kosong.)

    960/2* This question paper is CONFIDENTIAL until the examination is over.

    *Kertas soalan ini SULIT sehingga peperiksaan kertas ini tamat.

    [Turn over (Lihat sebelah)CONFIDENTIAL*

    SULIT*

    Identity card number:.....

    (Nombor kad pengenalan)

    Instruction to candidates:

    DO NOT OPEN THE BOOKLET UNTIL YOU ARE TOLD

    TO DO SO.

    Answer all the que stions i n s ection A i n t he s paces pr ovided. Allworkingmust be shown. For calculation, relevant values of constants in

    the data book let must be us ed. F or numerical answers, uni t must bequoted whenever they are appropriate.

    Answer any four questions from section B. For this section, write youranswers on t he ans wer sheets pr ovided. Begin each answer on a f resh

    sheet of paper, and arrange your answers in numerical order.Tie your answer sheets to this booklet.

    Answer may be written in either English or Malay.

    Arahan kepada calon:

    JANGAN BUKA KERTAS SOALAN INI SEHINGGA ANDA

    DIBENARKAN BERBUAT DEMIKIAN.

    Jawab semua soalan dalam b ahagian A da lam r uang y ang d isediakan..Semua k erja mestilah ditunjukkan. Bagi pe nghitungan nilai p emalar y ang

    berkaitan dalam Buku Data mestilah digunakan. Bagi jawapan berangka, unitmestilah dinyatakandi mana-mana yang sesuai.

    Jawap mana-mana empat soalan. dalam bahagian B. Untukbahagian ini, tulis jawapan andapada helaian yang dibekalkan. . Mulakan

    setiap j awapan pada h elaian kertas y ang ba ru, dan s usun jawapan andamengikut t ertib be rangka. I kat k ertas j awapan and a be rsama de ngan k ertas

    soalan ini.Jawapan boleh ditulis dalam bahasa Inggeris atau bahasa Melayu.

    CONFIDENTIAL*/SULIT*

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUAPERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    PERSIDANGANKEBANGSAANPENGETUA-PENGETUA PERSIDANGANKEBANGSAANPENGETUA-PENGETUA

    960/2 STPM TRIAL 2009

    PHYSICS (FIZIK)

    PAPER 2 ( KERTAS 2)

    STRUCTURE AND ESSAY (STRUKTUR DAN ESEI)

    Two and a half hours (Dua jam setengah)

    For examiners use

    (Untuk kegunaan

    pemeriksa)

    1

    2

    3

    4

    5

    6

    7

    8

    9

    10

    11

    12

    13

    14

    Total

    (Jumlah)

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    Section A [ 40 marks ]

    Answerallthe questions in this section.

    1. (a) Explain what is meant by work and power. [2]

    Work sFW

    =

    F = ForceS = displacement (1)

    Power is the rate of doing work. (1)

    (b) A car of mass 1540 kg is moving up a slope making an angle of 30o with the horizontal.

    The t otal a ir r esistance acting on t he c ar i s 500N. If the c ar i s m oving at a constant

    speed of 20.0 m s-1

    ,(i) calculate the force exert by the engine. [2]

    F = mgsin + R (1)

    = 540x9.81xsin30o + 500

    = 8054 N (1)

    (ii) find the power of the engine.

    P = Fv (1)

    = 1.61x105

    W (1)

    [2]

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    2. A uniform beam having a mass of 60 kg and a length of 2.8 m is held in place at itslower end by a pin. Its upper end leans against a vertical frictionless wall as shown inthe figure.

    (a) In the diagram below, show the direction of reaction forces acting on thebeam and the weight of the beam. [3]

    One mark for each direction.

    (b) What is the magnitude of the force the pin exerts on the beam? [3]

    Consider moment of forces about the pin :

    R1x2.8sin40o

    = Wx1.4cos40o

    (1)

    R1 = 350.7 N

    R2y = W = mg {1}= 588.6 N

    R2x = R1 (1)

    = 350.7 N

    NRRR yx 6852

    2

    2

    22 =+= (1)

    W

    R2

    40o

    R1

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    3. a) Based on a t hermodynamic l aw, explain the dr op in the t emperature of a ga s

    during an adiabatic expansion. [2]

    In an adiabatic expansion, no heat is absorbed or released by the system. (1)

    Therefore w ork i s done by us ing t he i nternal energy and t hus t he t emperaturedecreases. (1)

    Or From Q = dU + W

    Q = 0 (1)

    W = - dU ; thus temperature decreases. (1)

    (b) The following p-V graph represents a cyclic process in an ideal gas of constant mass.

    The overall process is represented by three separate changes I, II and III.

    i) Identify which change represents adiabatic change? [1]

    II

    ii) If the above processes represents the changes in a heat engine, in what sequence

    must the three processes take place? Explain how you deduce your answer. [2]

    II I III or clockwise (1)

    So that there is a net work done by the system. (1)

    P

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    4. (a) A sound source of a certain frequency moving towards a stationary observer. The

    frequency o f t he sound he ard by t he obs erver i s di fferent from t hat of t he s ource.

    Explain this phenomenon in terms of change in wavelength, frequency and velocity.

    [3 ]

    The apparent wavelength decreases. (1)

    But the velocity of the wave is unchanged. (1)

    From the equation , f = v/

    When the wavelength decreases, the apparent frequency increases. (1)

    (b) A car traveling normally towards a cl iff at a s peed of 30 m s-1 sounds its horn which

    emits a note of frequency 100 Hz. What is the frequency of the echo as heard by thedriver? (Speed of sound is 330 m s-1. ) [3]

    Hz

    x

    fuv

    uvf

    120

    10030330

    30330

    '

    =

    +=

    +=

    1

    1

    1

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    5. (a) A parallel-plate capacitor of capacitance Cand a resistor of large resistanceR are

    connected in series with a battery of e.m.f.Ehaving negligible internal resistance.

    (i) Sketch graphs to show the time variation of the voltage across the capacitor and the

    current in the circuit after closing switch S. [2]

    (ii) With switch Sclosed, the plates of the capacitor are pulled apart slightly. Describe and

    explain t he possible change(s) in the charge a nd the energy stored in the capacitor

    when the steady state is reached. [3]

    The charge decreases. (1)

    The energy stored also decreases. (1)

    Because the capacitance decreases but the potential difference is unchanged. (1)

    E

    00

    V

    I

    tt

    (1)

    (1)

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    6. You are given some isotopes of a certain element. The isotopes are ionized so that they can

    carry the same charge Q, and enter a speed selector as shown in the diagram below. Onlythose isotopes with a definite speed can pass straight through the mutually perpendicular

    uniform electric and magnetic fields in the speed selector. The whole set-up is in a

    vacuum environment.

    (i) Explain how the speed selector works. [2]In the speed selector, the electrostatic force and the magnetic force acting the charged

    particle are equal in magnitude but opposite in direction. (1)

    Therefore the resultant force is zero, thus the charge will move in a straight line. (1)

    Or qE = Bqv or FE = FB (1)

    F = 0 (1)

    (ii) Describe and explain how the isotopes can be distinguished experimentally by

    directing the emerging beam of ionized isotopes into a uniform magnetic field.

    [3]Different isotopes will be deflected in magnetic field in semicircular path of different

    radii. (1, 1)

    The mass of the isotope is directly proportional to the radius of the path. (1)

    Or Bqv = mv2/r (1)

    m r (1)

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    7. The diagram below shows two point charges,A andB, separated by a distance of 1.20 m

    QA = 1.50 10-6 C and QB= +4.20 10

    -6 C

    (a) Calculate the magnitude and direction of electric field at pointP, midway between thecharges. [3]

    Direction : BA (1)

    )1(1042.1)6.0(4

    102.4

    )6.0(4

    105.1

    )1(44

    15

    2

    6

    2

    6

    2

    2

    2

    1

    =+=

    +=

    Vmxxx

    r

    Q

    r

    QE

    oo

    o

    B

    o

    AP

    (b) Calculate the electric potential at pointP. [2]

    )1(1005.4

    )1(44

    4Vx

    r

    Q

    r

    QV

    o

    B

    o

    AP

    =

    +=

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    8. In an X-ray tube, electrons are accelerated towards an anode by a potential differenceof 10,500 V.

    (a)Calculate the de Broglie wavelength of the electrons just before collision withthe anode. [3]

    )1(1020.1

    )1(

    10073.62

    )1(

    111

    7

    2

    21

    =

    =

    ==

    =

    smx

    p

    h

    xm

    eVv

    eVmv

    (b) Calculate the minimum wavelength in the X-ray continuous spectrum. [2]

    )1(1018.1

    )1(

    10 mx

    eVhc

    =

    =

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    Section B [ 60 marks ]

    Answer anyfour questions in this section.

    9. (a) State Newtons Law of Universal Gravitation. [1]

    The gravitational attraction between two point masses is directly proportional to the

    product of the masses but inversely proportional to the square of their separation.

    (b) A satellite of mass 200 kg is placed in a circular orbit at a height of 200 km above the

    Earths equator travelling in the same direction as the rotation of Earth about its own

    axis.

    (i) Explain why the centre of the orbit must be at the centre of the Earth. [2]

    The weight of the satellite provides the centripetal force. (1)

    Since the weight acts towards the centre of the Earth, therefore the centre of the

    Earth is the centre of the orbit. (1)

    (ii) Calculate the speed of the satellite. [3]

    )1(/7800

    106.6

    )104.6(81.9

    )1(

    )1(

    6

    26

    22

    2

    2

    sm

    x

    xx

    gRGM

    r

    gRv

    r

    GMm

    r

    mv

    =

    =

    ==

    =

    (iii) The satellite passes a particular place on the ground at certain time of the day, by

    taking into account the rotation of the Earth, find the time interval it will pass the

    same place again ? [4]

    v = rw (1)

    15

    13

    6

    1027.7

    )1(2

    '

    10182.1106.6

    7800

    =

    =

    ==

    sradx

    TEarthofvelocityAngular

    sradxx

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    *This question paper is CONFIDENTIAL until the examination is over. CONFIDENTIAL*

    )1(56602

    10109.1

    )1('velocityangularRelative13

    sT

    sradx

    r

    r

    ==

    =

    =

    (iv) By ignoring air resistance, calculate the minimum energy required to launch the

    satellite into its orbit from the ground. [3]

    )1(1047.6

    7800200106.6

    1

    104.6

    1200)104.6(81.9

    11

    )1(

    )1(

    9

    2

    21

    66

    26

    2

    212

    2

    21

    Jx

    xxxx

    xx

    mv

    rR

    mgR

    mvr

    GMm

    R

    GMm

    EUW K

    =

    +

    =

    +

    =

    +=

    +=

    (v) What is the minimum speed of the satellite in the orbit so that it can escape from the

    gravitational field of the Earth and travel to infinity. [2]

    (Radius of Earth R = 6.40x106 m)

    )1(1010.1

    2

    )1(

    14

    2

    2

    21

    =

    =

    =

    smx

    r

    gRv

    r

    GMmmv

    10. a) The pressurep of an ideal gas of density is related to the mean-square speed ofits molecules by the expression

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    *This question paper is CONFIDENTIAL until the examination is over. CONFIDENTIAL*

    i) State three basic assumptions of the kinetic theory of gases, which lead to a model

    of an ideal gas [3]

    Any three of the followings:

    - The gas molecules move randomly in all direction.- The collisions between the molecules and the wall of the container

    are elastic.- There is no force between the molecules.- The time of collision can be neglected compared to the time between

    collisions.- The motion of gas molecules obeys Newtons Laws of motion.- The volume of the molecules can be neglected compared to the

    volume of the container.

    ii) Write down the equation for an ideal gas. Explain the symbols you use.

    [2]

    pV = nRT

    p = pressure of gas

    V = volume

    n = number of mole of gas

    T= temperature in Kelvin 2/0

    iii) Show that the average kinetic energy of a molecule of an ideal gas is proportional

    to the thermodynamic temperature T. [4]

    kT

    N

    RTcm

    nN

    nRT

    N

    nRT

    N

    PV

    cm

    cV

    NmP

    A

    A

    2

    3

    2

    3

    2

    1

    3

    3

    3

    3

    1

    2

    2

    2

    =

    >==

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    b) A tank contains 2.0 moles of helium gas at 200C. The molar mass of helium is 4.0 g.

    Assume that the helium gas behaves as an ideal gas

    i) find the total internal energy of the system [2]

    J

    nRTf

    U

    3704

    29331.822

    3

    2

    =

    =

    =

    ii) what is the average kinetic energy per molecule [2]

    J

    kTEK

    211007.6

    2

    3

    =

    =

    iii) determine the r.m.s. speed of the helium atoms at 200C. [2]

    12

    212

    23

    3

    212

    1350

    1007.61002.6

    104

    2

    1

    1007.62

    1

    =>==