CONFIDENTIAL *

JABATAN PEI,A.IARAN JOHORJABATAN PELAJAMN JOHOR.IABATAN PEI,A.IARAN.IOHOR.IABATAN

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Tbo and a half hours

tzj noursl

Instructions to candidates:DO NOT OPEN THIS BOOKLET TINTIL YOU ARE TOLD

TO DO SO.Answer all questions in Section A. Write your answers in the spaces

provided.Anrwer anyfout questions in Section B- Write your cmswers on the

answer sheets provided. Begin each answer on afresh sheet af paperand arrange your cmswers in numerical order. Tie your ctttrwer sheetsto this question paper.

AII working should be slnwn. For calculations, relevant values ofconstants in the Data Booklet should be wed. For numerical onswers,tmits should be quotedwherever they are appropriate.

Answer may be written in either English or Bahasa Malaysia

This question paper consists of 28 printed pages.

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

For examiner's useI234567891011t213t4

Total

CONFIDENTIAL*

CONFIDENTIAL *

Section A[44 mmks]

Answer all questions in this seciion.

1. (a) State the Principle of Conservation of Linear Momentum. ll mukl

(b) A bulletof mass 2.0 g is fired horizontally into ablock of wood 1.0 kg mass placedon a horizontal surface. The initial velocity of the bullet is 500 m s-t. The velocity of thebullet which comes out of the wooden block is 100 m s r. It is found that the *ood*block slides a distance of 0.20 m and stops. Determine(i) the velocity of the wooden block at the instant when the bullet emerges from it.

[2, marks]

(ii) the average frictional force between tte wooden block and the horizontal surface.12, marksl

2. An object is placed on the principal axis of a thin biconvex lens.The distance between theobject and the lens is 20 cm.The lens is made from glass of refractive index 1.65. The imageproduced by the lens is 0.25 times the size of the object.

(a) State whetherfie image is real orvirtual? ll markl

(b) Calculate the focal length of the lens. [2, marksl

(c) Determine the common radius of curvature for the surfaces of the lens.12. marksj

960n*This question paper is CONFIDENTIAL until the examination is over COI\FIDENTIAL*

(b) Sebutir peluru berjisim 2.0 g ditembak secara mengufuk ke dalam sebuah bungkahkayu berjisim 1.0 kg yang terletak pada suatu permukaan ufuk. Halaju awal peluru ialah 500 m s '.Peluru itu memuncul daripadabungkah kayu dengan halaju 100 ms-'. Didapati bungkah kayu itubergelungsur sejauh 0.20 m dan berhenti. Tentukan

COI\FIDENTIAL *

Bahagian A t4q markahi

Jaoab semuasoalon dalam bahagim ini

1. (a) Nyatakan Prinsip Keabadian Momentum Linear. ll mwkahl

(i) hal4iu bungkah kayu pada masa peluru itu memuncul. p markahl

(ii) min daya geseran antara bungkah kayu dengan permukaan ufirk. p, nnkahl

2. Sebuah objek dileak di atas paksi utama sebuah kanta dwicembung nipis. Jarak di antaraobjek dank anta ialah 20 cm. Kanta itu dibuat daripada kaca dengan indeks biasan 1.65.Saiz imejyang dihasilkan oleh kana itu ialah 0.25 kali saiz objek.

(a)Nyatakan sama ada imej itu adalah sahih atau maydl U nwkal\

(b) Kirakan panjang focus kanta itu. 12 mwkalil

(b) Tentukan jejari kelengkungan permukaan kanta dwicembung itu. pmarkalfl

960n*This question paper is CONFIDENTIAL until the examination is over COI{FIDENTIAL*

CONFIDENTIAL *

3. The graph below shows how the acceleration of an object undergoing simple harmonicmotion varies with time.

Acceleration /ms-2

50

0

-50

(a) Deduce from the numerical values gwen on the graph,

(i) the frquency ll nwlcl

(ii) the angular frequency ot ll mmkl

(iii) the amplitude xo of the oscillation. ll mokl

(b) Sketch a graph which shows how the displacement varies with time.ll mtkl

960D*This question paper is CONFIDENTIAL until the examination is over CONtrIDENTIAL*

CONFIDENTIAL *

3. Graf berikut menunjukkan bagaimana pecutan suatu objek yang melakukan gerakanharmonik ringkas berubah dengan masa.

Pecutan /ms-'

50

0

-50

(a) Berdasarkan nilai.nilai pada graph, tentukan nilai

(i) frekuensi ll nrknltl

(ii) frekuensi sudutco } nmkalfl

(iii) amptitude, xo ayunan tersebut. I nmkahl

O) satr graf untuk menunjukkan bagaimana sesaran objek itu berubah dengan'

ll nrkahl

960t2*This question paper is CONFIDENTIAL until the examination is over CONI:IDENTIAL*

COMIDENTIAL *

4. A glass fibre of length 0.24 mand area of cross-section 8.0 x 10-7 m2 is stretched until itbreaks. The variation with load Fof the extension x of the fibre is shown in the diagram below.

xll}am

4 t^--*"

40

I l i',14

F/I\{

(a) State with reason whether glass is ductile, brittle or polymeric. 12 mmksl

(b) Determine the Young's Modulus for the glass fibre. 13 marks)

96An*This question paper is CONFIDENTIAL until the examination is over CONFIDENTIAL*

COI\TFIDENTIAL *

4. Seutas gentian kaca dengan panjang 0.24 mdan luas keratan rentas 8.0 x l0-? m2diregangkan sehingg putus. Pemanjangan gentian ktc6x dengan perubahan beban F adalahseperti ditunjukkan di dalam grafberikut.

xll}am

4

3 l--

2

1

0 F/I{

(a) Nyatakan dengan memberikan sebab samada kaca adalah mulur, rapuh ataupolimerik. P markahl

(b) Tentukan nilai Modulus Young untuk gentian kaca itu. 13 rnarkaltl

960n*This question paper is CONFIDENTIAL until the examination is over CONtrIDENTIAL*

CONtrIDENTIAL *

5. (a) What is amultiplier? lL narkj

(b) State the function of a multiplier? ll markl

(c) A galvanometer of resistance 30 O has a full-scale deflection of 20 mA. It is tobe converted into a voltneter of range 0-3.0 V.Describe briefly, with the aid of a circuit diagram to show how a multiplier is connectedto the galvanometer and calculate the resistance of the multiplier required?

t3 marksl

DiaCra.m:

960D*This question paper is CONFIDENTIAL until the examination is over COI\FIDENTIAL*

CONFIDENTIAL *

5. (a) Apakah itapendarab? ll mwkalil

(;t il;; ;;il;;;;;;;;"s* .#;; ;d'd ;#;;"v' ;;;;;;;-il;i'-;k;i il;20 mA. Ianya hendaklah diubahsuai untuk menjadi sebuah voltneter denganrenj 0-3.0 V. Dengan bantuan satu gambarajah litar, huryikal secara ringkas bagaimana suatu

pendarab boleh diJambungkan kepada galvanometer dan kirakan nilai rintangan pendarab yang

iiperlukan. P mwkahl

Gambarajah litar:

(b) Nyatakan fungsi suatu Pendarab? l1 markahl

960D*This question paper is CONFIDENTIAL until the examination is over CONFIDENTIAL*

COI\FIDENTIAL *

6. (a) State one advantage ofusing negative feedback in an operationalamplifier.

IO

ll mrkl

In the op-amp circuit above, the input voltage V6(i) Calculate the closed loop gain of the circuit.

is sinusoidal with a peak voltage of 3.0 V.[1 mwkl

(b)

(ii) What is the ou$utvoltage, Vo? ll mmkl

(iii) Sketch two graphs to show the variation of Z6 and Vowithtime r on the same axes.p. marksl

960D*This question paper is CONFIDEN'TIAL until the examination is over COI\TFIDENTIAL*

60 hrf

:ov

Yi YO

tr

COI\FIDENTIAL *

6. (a) Nyatakan satu kelebihan suap balik negatif dalam litar op-amp. $ narkaltl

11

(b)

V

6S k!.f

Dalam litar op-amp di atas , voltan input V6 adalah sinusoidal dengan nilai puncak 3.0

(i) Kirakan gandaan gelung tertutup untuk litar ini. [1 markah]

(ii) Berapakah voltan outpuf Vo? fl markah)

(iii) Lakarkan dua graf untuk menunjulJcan bagaimana Ysdan Yoberubah dengan masa tpada paksi-paksi yang sama. p, markahl

960n*This question paper is CONFIDENTIAL until the examination is over CONFIDENTIAL*

! , -n.nl !q- .n, . r - . . . - .

i.----i.-""-i----i-*-'i

i'---'!'--.-'i'---'!'---':: :; : . : : :

COMIDENTIAL *

7. (This question is based on an experiment conducted by NASA on a novel source of

enerry for a space shuttle.)Abo; the equator of the Earth, the Earth's magnetic field runs horizontally in the south-

north direction.A space-shuttle flying from west to east above the equator cuts perpendicularly

across the magnetic nen as shown in the diagram below.A small satellite is at&ached to the

shuttle by a very long thin copper cable. It is proposed to use the e.m.f generated in the cable as

a source of electrical enerry for the shuttle. Magnetic flux

. -

into the paperz

(a) Explain how is there an e.m.f. generated in the cable? ll narkl

(b)Calculate tre magnitude of this e.m.f. using the followingdata:Cable length:20 kmSpeed of Jhuttle and satellite = 7.0 km s-rHorizontal component of the Earth's magnetic flux density: 6.0 x 10-5 T.

13 moksl

(c) State tre direction of the generated e.m.f. lI nokl

960n*This questionpaper is CONFIDENTIAL untilthe exanination is over COIIFIDENTIAL*

t2

shuttle

CONF'IDENTIAL * l3

7. (Soalan ini adalah berdasarkan kepada satu eksperimen y.angdirjalankangleh NASA )

Di atas khatulistiwa bumi, medan magnet Bumi adalah dalam arah Utara-Selatan.Satukapal angkasa terbang dari barat ke timur atas khatulistiwa dan memotong secam tegaklurusmedan magnet se'perti yang ditunjukkan dalam rajah di bawah.Satu satelit kecil disambungkankepada kapal angkasa dengan satu kabel kuprum yang halus dan panjang. Adalah dicadangkanuntuk menggunakan d.g.e. yang dijanakan dalam kabel sebagai punca tsnagaelekhik untuk kapalangkasa.

-/ Fluks magnet

I ke dalam kertasxx

x

Ikpal-angkasa

(a) Terangkan bagaimana suatu d.g.e boleh dijanakan dalam kebel? ll morkahl

(b) Kira magnitud d.g.e. tersebut dengan menggunakan data berikut :Panjangkabel :20kmLaju kapal angkasa dan satelit : 7 .0 km s-rKomponen ufuk ketumpakn fluks medan magnet Bumi:6.0 x 10'5 T. [3 nctrkah]

(c) Nyatakan arah d.g.e yang diianakan di dalam kabel itu. Il mukahl

950D*This question paper is CONFIDENTIAL untitr the examination is over CONFIDENTIAL*

COI\FIDENTIAL *

8. (a). Explain briefly what is meant by rurclearfusion. $ mmkl

(b). A carbon isotope tjC is bombarded with a proton to produce an unknown nuclide, X.

(i)Write a nuclear equation to represent tre above reaction and identif,i the unkownnuclide, X. [2. marksl

(ii) Calculate the enerry released during the reaction.Massof t lc :13.003355u, massof lH: t .ooztzsuMass ofunknoum nuclide.X = 14.003074 ulu = 931 MeV [2 narks)

960n*This question paper is CONFIDENTIAL until the examination is over CONFIDENTIAL*

t4

COMIDENTIAL *

8. (a). Terangkan secara ringkas apa yang di maksudkan dengan pelakuran nuklear ?p markahl

(b) Satu isotop karbon tl C OiUeal oleh satu proton dan menghasilkan satunuklid anu, X.

(i) Tulis satu persamaan nuklear untuk mewakili tindakbalas di atas dan camkan nuklidanu X. p mukalfl

(ii) tenaga yang dibebaskan dalam tindakbalas ini. V. narkalil

risim tlC : 13.003355u, jisim lu: t.ooztzs uJisim nuklid anu: 14.003074 uI u=931MeV

960D' *This question paper is CONFIDENTIAL until the examination is over COIYFIDEIYTIAL*

i15

COMIDENTIAL *

Section B 160 marksl

Answer mty fou.r questions in this section

9. (a). What is meant by centripetal force ? ll markl

(b). A student suggests that for a body to perform circular motion, the centipetal force actingtowards the centre of the circle is balanced by the centrifugal force acting outwards awayfrom the centre of the circle. Comment on the above statement

p mmksl

(c). A car goes over a hump of radius of curvature l0 m. What is the maximum speed of thecar so that it is always in contact with the road ? [3 mmks]

(d) (i) State Newton's Law of Universal Gravitation. Il mmkl

(ii) A satellite of mass m goes round a planet of mass M n an orbit of radius r.If G is the universal gravitational constant, what is the gravitational force of athactionbetween the planet and the satellite ? p mmksl

T6

(e) A satellite of mass 150 kg goes round the ear*r in a circular orbit of radiustwice the radius of the earth. Calculate ,(i) the centripetal force acting on the satellite.

(ii) the orbital period of the satellite.

(Radius of the earth = 6.38 x 106 m)

13 mmksl

13 mwksl

960n*This question paper is CONFIDENTIAL until the examination is over COI\FIIIENTIAL*

COMIDENTIAL *

Bahagian 8160 marksl

Jswab m(ma-m(ma empat soalan dalam bahagian ini.

9 (a) Apakah yang dimaksudkan oleh daya memusat ? [ mctrkah]

(b) Seorang pelajar mencadangkan bahawa supaya sesuatu jasad melakukangerakan membula! daya memusat yang bertindak ke pusat bulatan diimbangioleh daya emparan yang bertindak ke luar pusat bulatan. Komen tentangkenyataan di atas. 12 nwkah)

(c) Sebuah kereta melalui sebuah bonggol dengan jejari kelengkungan l0 m.Apakah laju maksimum kereta supaya ia sentiasa bersentuhan dengan jalan.

[3 markah]

(d) (i) Nyatakan Hukum Semesta Kegravitian Newton llmmkahj

(ii) Satu satelit berjisim m mengorbit sebuah planet berjisim M dalam satuorbit berjejari r. Jika G adalah pemalar Graviti Semesta" apakah dayatarikan antara planet dan satelit ? t2 narkahl

(e) Satu satelit berjisim m mengorbit bumi dalam satu orbit berjejari dua kalijejari bumi. Kira(i) daya memusatyang bertindak pada satelit, 12 markahl

(ii) tempoh satelit ini, 13 markahl

(iii) tenaga kinetik satelit. t2 mmkahl

I Diberijejari Bumi:6.38 x 106 m ]

960D*This question paper is CONFIDENTIAL until the examination is over COI\TFIDENTIAL*

t7

COMIDENTIAL *

10. (a) Metals are good conductors of both heat and electicity while good thermal insulatorsare also good electric insulators. Explain why? 13 marksl

(b) The rate of heat flow througlr a well-lagged metal rod at steady state is defined by the

. o . .d0equation - =-kt4- ,' t&

where Q is the quantity of heat flow, ft is the thermal conductivity of the metal ,l is the

cross-sectional area of the rod and 4 *the temperatwe gradienl alongthe rod.dx

(r) Explain what do you understandby steady state and tenpetature gradientl[2 marks]

(ii) Based on the statement in (a) aboveo state the quantities in electric conduction formetals that are analogous tD rate of heat JIow and temperature gradient in thermalconduction for metals. p mnksl(iii)Hence write an equation for electric conduction that is equivalent to the equation ofheat flow as in (b) above. Explain the symbols used in your equation.

12 marksl

(c) The diagram below shows two rods of the same length, L anddiameter but madefrom two different materials P and Q. They are flaced end to end in thermal contact andwell lagged at their sides. The outer ends of P and Q are kept at OoC and 100"Crespectively. The therrnal conductivity of P is four times that of Q.

00c 1000c

/r* lagggrng

(i) Determine the steady-state temperature at the jointed-end. 13 marksl(ii)Sketch a Saph to show the distribution of steady-state temperature along the wholejointed rod. 13 matksl

960t2*This question paper is CONFIDENTIAL until the examination is over COI\tr'IDENTIAL*

l8

COI\tr'IDENTIAL *

10. (a) Logam adalah pengkonduksi haba dan elektrik yang baik manakalapenebat therma adalah juga penebat elektrik yang baik.Jelaskankenap 13 mmkahl

(b) Kadar pengaliran haba melalui sebuah rod logam y4ng ditebat sempurna

pada keadaan mantap diakrifkan oleh persam *, 9- : - kA ( , U^^a Q adalahkuantititdx

haba yang mengalir, k ialahkekonduksian terma logam itu, A ialah luas keratan rentas rod dan

( adatahkecerunan suhu sepanjang rod.ax

(i) Terangkan apa yang dimaksudkan oleh keaadaan mantap dan kecerunan suhu[2 mmkah]

(ii) Berdasarkan pada kenyataan (a) di atas , nyatakan kuantiti dalam konduksielekhik yang beranalogi dengan kadar pengaliran haba dan kecerunan suhu dalam konduksiterma. [2 markah]

(iii) Seterusnya" tuliskan satu persamaan untuk konduksi elektrik yang setaradengan persamaan pengaliran haba dalam (b) di atas.Jelaskan simbol-simbol yang digunakandalam persamaan anda. p narkahl

(c) Rajah di bawah menunjukkan dua rod yang sama panjang, L dan diametertapi diperbuat daripada bahan yang berlainan P dan Q. Mereka diletakkan, hujung ke hujungdalam senhrhan terma dan ditebatkan baik pada sisinya. Sisi-sisi luar P dan G ditetapkan pada0"C dan 1000C masing-masing. Kekonduksian tenna P adatah 4 kali kekonduksian tirmaQ.

1000c

fu penebatan

(i) Tentukan suhu mantap pada hujung yang disambung. 13 markahl(ii) Lakarkan graf untuk menunjukkan perubahan suhu disepanjang rod bersambung itu

13 narkahl

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

L9

00c

COhIFIDENTIAL *

11. (a) State two conditions necessary to produce a well-defmed stationary wave using twoseparate sound sources. 12 narksl(b)The equation of a stationary wave on a stretched string is given as:

! = 0.1sin 250/ cos 50r

where distances are in mefes and time is in seconds.(i) Calculate the frequency of this wave.(ii) Wha! is the distance between trvo neighbouring nodes along this waves.

(iii) Calculate the speed of the wave in this string.

(c) (i) What do you understand by interference.

(ii)State two conditions necessary to produce a well-defined interference pattern.[2 marks]

(d) The appaxatus of a Young's double-slits experiment is set up as shown below. G isequidistant from the double-slits 51 and Sz. H is a point on the screen when the light

waves from Sr and Sz interfere with a path differeor" of {.2

(i) What is the type of interference observed at G and at H respectively? pmorksl(ii) If the distance SrSz= 1.0 mm, D=I.50 m and the wavelength of the lidht" A is 600 nm,calculate the value of v. p marksl

960n*This question paper is CONFIDENTIAL until the exanination is over COITFIDENTIAL*

20

12 marksl

p marksltl marn

ll mmkl

COI\FIDENTIAL *

11. (a) Nyatakan dua syarat yang diperlukan supaya boleh menghasilkan gelombang pegunyang jelas oleh dua punca gelombmg bunyi yang berasingan. p nokall

(b) Persamaan yang mewakili suatu gelombang pegun pada satu tali teregang adalahseperti berikut:

2l

! = 0.1sin 250/ cos 50x

dimana ukuran jarak adalah dalam metre dan masa dalam saat.(i) Tentukan fr,ekuensi gelombang ini.

(iii) Kirakan laju gelombang dalam tali teregang ini.

(c) (i) Apakah yang anda faham dengan interferens.

12 mmkal\(ii) Berapakah jarak di antara duanod berturut sepanjang gelombang pegun ini.

p nokahlll nwkahl

[l narkafl

(ii) Nyatakan dua syaratyang diperlukan untuk meng&asilkan corak interferens yangjelas. t2 narkahl

(d) Radas-radas untuk me'ngkaji interferens dwicelah Young adalah disusun seperti dalamgambarajah b€rikut. G adalah sama jarak dari dwicelah Si dan 52. H ialah satu"titik pada skrin di

mana gelombang cahaya dari Sr dan 52 bertindih dengan bezajarak sebanyak {.'2

(i) Apakah jenis interferens yang berlaku pada G dan H masing-masing?

(ii) Jika jarak S1S2= I .0 mm, D=l .50 m dan panjaqs gelombang A ial,ill 600 ":,

mf#nilai untuk y. 13 mmkahj

96012*This question paper is CONFIDENTIAL until the examination is over CONFIDENTIAL*

X :l

22

t2.

CONIIIDANTIAL *

gravitational.

(c) Neon-20 atoms areNeon-20 ion,(i) state the charge on the ion.(ii) calculate its mass.

above.

(ii) the path of the ions in the region of the electric and magnetic fields.

(a) A stationary negatively-charged particle experiences 1fo.T in the direction of the

ii"f6 io which ii is ptaced. State and explain, whether the freld is magnetic, electric or

(b) Calcutate the magnitude ofthe electric field sftength required to maintain an electron

in a fxed position in the gravihtional field of the Earft, at its surface.

(Take g:9.81 ms-' ; mass of electron:9.1 x 10rt kg; V noh"sl

ionized by the removal of one electron from each atom. For a

[2 notu]

ll marklpmorksl

(d) The neon ions in (c) are accelerated from rest in vacuum ttrough a potential

dii1"rro"" of 1400 V.They are then injected into a region of space where there are

uniform electric and magnetic fields acting at right angles to the incident direction of

motion of the ions as shown in the following diagram. The electric field has field strength

E andthe flux densrty ofthe magnetic field is -8.

Region of uniformelectric and magneticfields

Path of neon ions

(i) Draw and indicate clearly the directions of the electric and magnetic fields solhat the

irrrr purr through undeflected through the region. 12 marlal

(ii)Calculate the speed of the accelerated ions on entry into ttre region of the electric and

magnetic fields. 12 marksl

(iii) The electric field strength Eis 6.2x 103 Vm-l. Calculate the magnituO"-"1F"magnetic flux density so that the ions are not deflected in the region of the fields.

12 mark{

(e) The mechanism by which the neon atoms in (c) are ionized is changed so that each

atom loses two electrons. State and explain what change occurs in:(r) the speed of the ions entering the region of the electric and magnetic fields as in (d)

ll narkl

ll markl

960n*This question paper is CONFIDENTIAL until the examination is over COI\tr|:IDENTIAL*

COI\'FIDEI{TIAL *

12. (a) Satu zarah pegun bercas negatif mengalami suatu daya dalam arah yang sama denganarah medan dalam mana ia diletakkan. Nyata dan terangkan,, sama ada medan itu adalah medanmagnet, medan elelctrik atau medan graviti. p marknhJ

23

O) Kirakan magnitud kekuatan medan elektrik yang diperlukan untuk mengekalkan satuelektron supaya b".qdu pegun dalam medan gayrry di permukaan Bumi.(Ambil g:9.81 ms-' ; jisim elektron = 9.1 x 10'" kg) p markahl

(c) Atom-atom Neon-20 boleh diionkan dengan mengeluarkan satu elekkon daripadasetiap atom. Bagi satu ion Neon-20,

(i) nyatakan casnya(ii) tentu jisimnya

[1, mmkafl12 mmkahl

(d) Ion-ion Ne dalam (c) dipecutkan daripada keadaan pegun dalam vakum dengan bezakeupayaan 1400 V.Mereka kemudiannya dimasukkan ke dalam satu kawasan yang mempunyaimedan elektrik dan medan magnet yang saling berserenjang kepada arah tuju alur ion seperti didalam gambarajah berikut. Kekuatan medan elektrik ialah Edan ketumpatan fluks medan magnetialah B.

Kawasanmedaneleknik dan magnetyang saling serenjang

(i) Lukis dan tunjukkan dengan jelas arah-axah medan elektrik dan rnedan magnet supayaion-ion melepasi kawasan tanpa pesongan. p markahl

(ii)Tentukan laju ion semasa memasuki kawasan medan elekhik dan medan magnet"p markahl

(iii) Kekuatan medan elellrik E ialah 6.2 x 103 Vm-t. Kira magnitud ketumpatan fluksmedan magnetB supaya ion-ion tidak dipesongkan semasa di dalam kawasan dua medan itu.

12 mdralil

(e) Proses pengionan atom-atom neon dalam (c) diubah supaya setiap atom dikeluarkandua elekmon. Nyata dan terangkan apa yang berlaku kepada:

(i) laju ion semasa memasuki kawasan medan elektrik dan medan magnet dalann (d) diatas. fl mmkalfl

(ii) rentasan ion-ion di dalam kawasan medan elekhik dan medan magnet.I markah]

soatltirpfrp ir CONFIDENTTAL until the examination is over COIIFIDENTIAL*

COhIFIDENTIAL *

13. (a) What do you understand bV (i) de Broglie's relationship (ii) wave-particleduality ? 12 marksl

(b) What is the de Broglie wavelength of an electron which has a kineticenerry of50 eV ?

(c) Explain the differences between the production of the continuousspeotum and the characteristic spectrum of X-rays.

(d) Sketch a suitable graph to show fie continuous and characteristicline spectrum of the X-rays produced when a metal target isbombarded by energetic elecfons

(e) Explain why for an elertron of e,nerry E, the wavelength of the X-raysproduced has a minimum value , 1,^

(f) Calculate the shortestwavelength of X-rays emitted by elecfonsstriking the surface of a 20kV television picture tube.

[m" = 9.11 x 10-31 kg Planck constant = 6.63 x 10-341

12, marlul

p marh"sl

p narksl

12nqksl

[3 nsksl

960n*This question paper is CONFIDENTLAL until the examination is over COIIFIDENTIAL*

24

COIYFIDENTIAL *

13. (a) Apakah yang anda fahamkan dengan (i) hubungan de Brogliezarah.

25

(b)Berapakah panjang gelombang de Broglie untuk satu elektron yangmempunyai tenaga kinetik 50 eV ?

(c) Terangkan perllrzm diantara mekanisma penghasilan spektrum selanjardan spektrum ciri bagi sinar X.

(d) Lakarkan safir grafyang sesuai untuk menunjukkan spektrum selaqiardan spekrum ciri sinarX yang dihasilkan apabila satu sasaran iogu-dibedil oleh elektron 1ag bertenaga tinggr.

(e) Jelaskm m€ngapa untuk satu elekFon yang bertenagaB,panjang gelombmg sinar X yang dihasilkan mempunyai nilai minimuml f f i .

- (D 5!. panjang gelombang yang terpendek sinar X yang

dihasilkan oleh elekhon-elekbon yang menghe,ntam permukaan strin ai dalam tiubtelevisyen yang berkadar 20 kv. t3 markah!

(ii) kedualan gelombang-p, mmkahl

[2 markah]

IA mctrkalt]

p narkafl

p makahl

}

,TIAL until the examination is over COIIFTDENTIAL*

CONtrTDENTIAL *

14. (a) Defme the half-life and decay constant of a radioactive substance' 12 marksl

(b) Nahrrally occurring radfi,m-226 with atomic number 88 produces the radioactive gas

ll mwkl13 nnksl

p marksl

L2, marksl

p marksl

26

radon-222 by alpha decay.(0 Write an equation for the decay process(ii) Cabutate the total kinetic energy of the decay products in MeV

Mass of radium :226.025402 u, mass of radon :222'017570 u

Mass of helium:4.002603 u lu = 931 MeV

(c) The bombardment of a beryllium nucleus by an alpha particle produces a frrndamental

particle X, as follows

d+noBe* t lc+x

(i) Complete the above equation

(ii) What are the alpha particle and X ?

(iii) State two important properties which makes X difficult to detect.

(d) An ion of unknown atomic mass is mixed wi*r 1l C in a mass spectrometer. The radii

of curvature of the tracks of the iong and tic "r"

26.2 cm and22.4 cm respectively. What is the

identity ofthe unknown ion ? State any assumptions that you make' 13 msksl

960n*This question paper is CONFIDENTIAL until the examination is over COMIDENTIAL*

,J

O(XFIDEXTTTIAL *

f( (a) Takrifkan separuh hayat dan pemalar susutan sesuatu bahan radioaktif.p markahl

(b) Radium-226 senulajadi dengan nombor atom 88 menghasilkan gasradioakf,if rad on-222 dengan reputan alfa.

(i) Tulis satu persamaan untuk proses reputan ini. ll markahl

(ii) Kira jumlah tenaga kinetik bagi produk-produk reputan ini dalam MevB markahl

Jisim radium =226.,.025402 u, jisim radon = 222.0175j0 uJisim helium = 4.A026A3 u , lu = 931 MeV

(c) Pembedilan satu nukleus beryllium dengan satu zarah alfa menghasilkan

satr zarah asas X, seperti berikut :

d +|Be-+' lc+x

(i) Leagkapkan persamaan di atas. p markah]

Cn) Apa diazarah alfa dan zarahx. [z mortrah)

CliD l-IJ&kan dua sifat penting kenapa zamh x susah dikesan . I2narkahl

(o sfi inn dengan jisim atom anu telah dicampurkan dengan tlc dalam

rchrh spekfiometer jisim. Jejari-jejari kelengkungan runut-runut

in dm tlC uOut"t 26.2 cm dan 22.4cm masing-masing. Apakah

ifetiti ion anu itu ? Nyatakan anggapan yang anda buat [3 mukall

efl!*Thiltqr.Cff{FIDFiTIAL rmtil the examination is over COI\trIDENTIAL*

2i

COMIDENTIAL *

Spodof lightin free sPace

Permeability of free sPace

Permirivity of frm sPace

I{ryritude of elecfionic charge

Planckconstant

Unifid atomic mass consbnt

Restrmsofelstnn

Rcstmsofproton

Molargu constant

Avogadro constant

Bolhnumconshnt

Gravihtimal constant

Acceleration of free fall

g60PEYSICTVrluesof constrnh

zt

c

Ih

h

3.00x l08msl

4rx 10'7Hrnr

8.85 x lCIrz Frnr

(l(36n)xl04Fnr

1.60x l0reC

6.63x10'ilIs

l.ffi x l0'1?S

9.ll x 10{rS

1.6? x l0'tkg

8.31 I Kr moll

6.02 x lf mofl

1.38x l0{3JKl

6.6? x l0{'N*tkgt

9.81mst

x

e

h

u

W

mp

ntr,llr

k

G

g

960D*This question paper is CONFIDENTIAL until the examination is over CONtrIDENTIAL*