multiple choice competition, 9 ijso, tehran, i.r.of iran...
TRANSCRIPT
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 1
EXAMINATION RULES
1. All competitors must be present at the front of examination room ten minutes before the
examination starts.
2. No competitors are allowed to bring any tools except his/her personal medicine or any
personal medical equipment.
3. Each competitor has to sit according to his or her designated desk.
4. Before the examination starts, each competitor has to check the stationary and any tools (pen,
ruler, calculator) provided by the organizer.
5. Each competitor has to check the question and answer sheets. Raise your hand, if you find
any missing sheets. Start after the bell rings.
6. During the examination, competitors are not allowed to leave the examination room except
for emergency case and for that the examination supervisor will accompany them.
7. The competitors are not allowed to bother other competitor and disturb the examination. In
case any assistance is needed, a competitor may raise his/her hand and the nearest supervisor
will come to help.
8. There will be no question or discussion about the examination problems. The competitor must
stay at their desk until the time allocated for the examination is over, although he/she has
finished the examination earlier or does not want to continue working.
9. At the end of the examination time there will be a signal (the ringing of a bell). You are not
allowed to write anything on the answer sheet, after the allocated time is over. All
competitors must leave the room quietly. The question and answer sheets must be put neatly
on your desk.
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 2
Read the following instructions carefully:
1. The time available is 3 hours.
2. The total number of the questions is 30. Check that you have a complete set of the test
questions and the answer sheet.
3. Use only the pen provided.
4. Write down your name, code, country and signature in your answer sheet.
5. Read carefully each problem and choose your correct answer by crossing one of the capital
letters in your answer sheet. There is only one right answer for each problem.
Example:
1 A B C D
6. If you want to change your answer, you have to circle the first answer and then cross a new
letter as your correct answer. You are only allowed to make one correction.
Example:
1 A B C D
A is the first answer and D is the corrected answer
7. All competitors are not allowed to bring any stationary and tools provided from outside. After
completing your answers, all of the question and answer sheets should be put neatly on your
desk.
8. Grading rules:
Correct answer : + 1.00 point
Wrong answer : : - 0.25 point
No answer : 0 point
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 3
1. A block of 0oC ice with the mass of 50 kg slides on a horizontal surface. The initial velocity of
ice is 6.0 m/s and it stops after a distance of 28.3 m. How much ice melts due to the friction?
(specific latent heat of fusion of ice, Lf = 80 cal/g and 1 cal = 4.18 J and neglect the heat
transfers to the environment)
50 kg agirligindaki sicakligi 0 0C olan bir buz kutlesi yatay bir duzlem uzerinde kayiyor. Buzun
ilk hizi 6m/s ‘ dir ve buz 28.3 m yol aldiktan sonar duruyor .Surtunmeden dolayi kac gram buz
erir?
(Lf=80 kal/g ve 1 kal =4.18 j )(cevreyle olan isi alisverisi onemsenmiyor )
(a) 47 g (b) 2.7 g (c) 4.7 g (d) 11.2 g
2. Why does the Moon always show its same face to Earth? Because:
(a) it rotates about its axis almost once per day
(b) it rotates about its axis almost once per month
(c) it rotates about its axis almost once per year
(d) it does not rotate about its axis
Ay nicin her zaman dunyaya ayni yuzunu gosterir .Cunku ,
a) Kendi ekseni etrafinda donusunu yaklasik 1 gunde tamamlar
b) Kendi ekseni etrafinda donusunu yaklasik 1ayda tamamlar
c) Kendi ekseni etrafinda donusunu yaklasik 1 yilda tamamlar
d) kendi ekseni etrafinda donmez
3.The following diagram shows changing force which is applied to a body with a mass of 5 kg in the
same direction. The body is initially at rest. What is the final speed in m/s after 2.5 s?
Asagidaki grafik 5 kg lik bir cisime ayni yonde uygulanan degisken bir kuvveti gostermektedir.Cisim
basta hareketsizdir. 2.5 saniye sonaraki son hizi kactir?
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 4
(a) 4 (b) 6 (c) 8 (d) 10
4. A light beam from a laser source which is parallel to the horizontal surface, hits an equilateral
prism as shown in the figure below. What is the angle α (between AB and the horizontal surface) if
the emergent beam is perpendicular to the face AB? (Refractive index of the prism is 2)
Yatay duzleme parelel olarak gelen lazer isini eskenar bir prizmaya asagidaki sekildeki gibi carpiyor.
Eger prizmadan cikan isin AB yuzeyine dik ise alfa acisi (AB ile yatay duzlem arasindaki aci ) nedir
(prizmanin kirilma indisi = 2 )
(a) 24.5o (b) 42.5o (c) 15o (d) 30o
5. An ambulance moves through a street along the positive X direction and a person who stands
beside the street hears the sound of the ambulance siren. Which option represents the frequency(f)
received by the person? X is the position of the ambulance; the person stands at the origin.
Bir ambulans cadde boyunca +X yonunde hareket ediyor ve caddenin kenarinda duran bir adamda
ambulansin sirenini duyuyor .Asagidakilerden hangisi adamin isittigi sesin frekansini gosterir.( X
ambulansin yeri , orijin noktasida adamin yeridir
f
X
f
X
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 5
(a)
(b)
(c)
(d)
6. In the Track and Field World Championships, the world record in the 100-m dash was as shown in
the table. Which of the following graphs best represents the time variation of velocity?
Track ve Field dunya sampiyonasinda yuz metre kisa mesafe dunya rekoru asagidaki tabloda
verilmistir.Asagidaki grafiklerden hangisi hizin zamana gore degisimini gosterir.
t (s) 1.88 2.96 3.88 4.77 5.61 6.46 7.30 8.13 9.0 9.87
x (m) 10 20 30 40 50 60 70 80 90 100
(a)
`
(b)
f
X
f
X
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 6
(c)
(d)
7. The vertical surfaces of a frustum (as shown below) are connected to two thermal reservoirs at
different temperatures. The material is solid and uniform. Which diagram shows the temperature
variation along the frustum axis after temperature stabilization?
Asagida gorulen kesik piramidin iki dik yuzeyi farkli sicakliktaki iki ayri isi kaynagina
baglanmistir.Kullanilan materyal kati ve tek cinstir. Asagidaki grafiklerden hangisi kesik piramidin
denge sicakligina ulastiktan sonraki sicaklik dagilimini gosterir.
(a)
(b)
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 7
(c)
(d)
8. The following figure shows a barometer, the cross section area of each pipe is 1.8 cm2. The
barometer contains the fluid with density of 8 g/cm3.
The barometer is connected to a gas tank. The right pipe is closed and above the fluid is vacuum.The
height difference between the liquid levels in the two pipes equals to 0.25 m.
What is the weight of liquid (between the two AB & CD levels)? What is the ratio of the gas pressure
to the atmosphere pressure? g= 10 m/s2
Asagidaki figur her bir borusunun kesit alani 1.8 cm2 olan bir barometreyi gosterir. Barometrenin
icinde yogunlugu 8 g/cm3 olan bir sivi vardir.Barometre bir gaz tankina baglanmistir .Sagdaki boru
kapali ve sivinin uzeri bosluktur. Iki borudaki sivi seviyeleri arasindaki fark 0.25 metredir. Sivinin
agirligi kactir.(AB ve CD seviyeleri arasindaki sivi )ve tanktaki gazin basincinin atmosfer basincina
orani kactir.
(a) 2,6.3 N (b) 2.0,6.3 N (c) 2,36N (d) 2.0,36N
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 8
9. A word is written in blue ink on a white sheet paper. A red light illuminates this paper and
(A) The word is seen red
(B) The word is not seen
(C) The word is seen black
(D) The word is seen blue
Beyaz bir kagidin uzerine mavi murekkeple bir kelimi yazilmistir.Kirmizi bir isik kagidi
aydinlatmaktadirve
A) Kelime kirmizi gozukur
B) Kelime gorunmez
C) Kelime siyah gorunur
D) Kelime mavi gorunur
10) In the following circuit, what is the ratio of equivalent resistance when the switch (k) is closed to
switch (k) is open? If the total current through the circuit is” I”, when the switch is opened, what
fraction of “I” is shown by the Ammeter (A)?
Asagidaki devrede K anahtari kapatildiginda olusan esdeger direncin , K anahtari acildiginda olusan
esdeger dirence orani kactir ? Eger devredeki ana akim I ise anahtar acildiginda ampermetrenin
gosterdigi deger I nin kacta kacidir ?
(A) I50
12,0 (B) I
19
2,0 (C) I
25
12,
50
12 (D) I
25
12,0
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 9
A
C1
1
2
k
Ω
Ω
Ω
4
12
Ω
Ω
B
1Ω
I
2Ωi
11)The Density of hot and cold water are different mainly because:
Sicak suyun yogunlugu soguk sudan daha buyuktur cunku
(A) The molecules in hot water are slightly larger than in cold water.
Sicak sudaki molekuller soguk suda molekullerden biraz daha buyuktur
(B) The bond between hydrogen and oxygen atoms in a single water molecule is stronger in cold
water
Soguk sudaki , tek su molekulunde bulunan hidrojen atomlariyla oksijen atomlari arasindaki
bag daha gucludur
(C) The molecules in hot water move faster and are slightly further apart.
Sicak sudaki molekuller daha hizli ve birbirinden azda olsa uzaktirlar
(D) Intermolecular forces in cold water are weaker.
Soguk sudaki molekuller arasi kuvvetler daha zayiftir
12)When certain substances dissolve, the solution gets colder. This type of dissolving process is
endothermic. In endothermic dissolving:
Belli miktarda madde cozuldugu zaman ,cozelti soguyorsa b u tur cozulmelere endotermik
cozulme denir .endotermik cozulmelerde :
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 10
(A) More energy is released when solvent molecules bond to the solute than is used to pull the
solute particles apart.
cozucunun molekulleri cozunenin molekullerine bag kurarken aciga cikan enerji cozucu
molekullerinincozunen molekullerini birbirinden uzaklastirmasi icin kullanilan enerjiden
daha fazladir
(B) More energy is used to pull the solute particles apart than is released when solvent molecules
bond to the solute.
cozunenun molekulleri birbrinden uzaklasmasi icin harcanan enerji cozucunun ve
cozunenin molekullerinin arasinda bag olusurken aciga cikan enerjiden daha fazladir
(C) More energy is used when the solute molecules get apart than to pull the solvent molecules
apart.
Cozunenin molekulleri birbirinden uzak durmasi icin kullanilan enerji cozucunun
molekullerinin cozunen molekullerini birbirinden uzaklastirmasi icin gereken enerjiden daha
fazladir
(D) The energy released when solvent molecules get apart is more than the energy released when
solute molecules bond to solvent.
Cozunenin molekulleri birbirinden uzaklasirken aciga cikan enerji cozucunun
molekullerinin cozunen molekulerine baglanirken aciga cikan enerjiden daha fazladir
13)Consider the following aqueous equilibrium ;
HF H+ + F-
In which of the following answers both of the compounds would decrease the amount of HF in
equilibrium, when added to the solution ?
Verilen denge reaksiyonununa gore
HF H+ + F-
seceneklerde verilen her iki bilesik eklendiginde , dengedeki HF madde miktarini azaltir
(A) NaCl , CaCl2
(B) NaF, NaOH
(C) H2O, NH3
(D) CaF2 , H2SO4
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 11
14)In four containers with equal volume and temperature, equal masses of the gas mixtures below is
confined. Which container would have the highest pressure? The compositions are given in mole
percent
Esit hacim ve sicakliktaki 4 kapta , toplam kutleleri ayni olan gas karisimlari vardir .Verilen mol
yuzdelerine gore hangisinde basinca en fazladir .
(A) 50% He, 50% Ne
(B) 50% He, 50% Ar
(C) 70% Xe, 30% Ne
(D) 90% Xe, 10% Kr
15)50 mL of 0.1 M Ammonia solution is being titrated with a standard 0.1 M HCl solution. Which of
the following acid-base indicators is the most accurate to reveal the equivalent point ( pKa of NH4+
ion is 9.2)?
50 mL 0.1 M amonyak cozeltisi standard 0.1 M HCl cozeltisiyle titrasyon ediliyor .Kullanilmasi
gereken en iyi indikator secin ( pKa of NH4+ ion is 9.2)?
(A) Phenolphthalein which changes color between pH =8.2 to 10.0
(Phenolphthalein rengi pH 8.2 - 10.0 arasinda degisir )
(B) Methyl Red which changes color between pH=4.8 to 6.0
(Methyl Red rengi pH= 4.8 -6.0 arasinda dedisir )
(C) Bromothymol Blue which changes color between pH=6.0 to 7.6
(Bromothymol Blue rengi pH 6.0-7.6 arasinda degisir )
(D) Methyl Orange which changes color between pH=3.2 to 4.4
(Methyl Orange pH 3.2-4.4 arasinda rengi degisir )
16) Carbon monoxide and Chlorine react to form Phosgene, COCl2. A mixture was prepared
containing 0.20 mole of CO and 0.10 mole of Cl2 in a 3.0 dm3 vessel at 400K. The equilibrium
constant for the reaction, Kc=0.41.
What would be the number of moles of COCl2 at equilibrium ?
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 12
Karbon monoksit gazi ile klor gazi reaksiyona girdiklerinde fosgen gazi COCl2 olusuyor .0.2 mole
karbon monoksit ile 0.1 mol klor gazi reaksiyona girdiklerinde dengede olusan fosgen COCl 2
gazinin molekul sayisi nedir .Bu reaksiyonun denge sabiti 0.41 dir.
(A) 8.75x10-4 mol
(B) 2.92x10-4 mol
(C) 2.63x10-4 mol
(D) 2.63x10-3 mol
17) What is the correct order for the bond energy in the following molecules ?
Asagidakiler hangisi molekullerin bag enerjisini dogru sirada veriyor .
(A) CO2 > CCl4 > N2 > CH4
(B) N2 > CO2 > CCl4 > CH4
(C) CO2 > N2 > CCl4 > CH4
(D) N2 > CO2 > CH4 > CCl4
18)Assuming that all reactions go to completion, which of the compounds below would release more
CO2 molecules if we heat the amount indicated in parentheses ?
Asagidakilerin hangisinde agirliklari parantez icinde verilen maddelerin parcalanmasindan en fazla
C02 gaz molekulu olusur
(A) BaCO3 (1.0 g)
(B) Li2CO3 (2.0 g)
(C) Ce(CO3)2 (3.0 g)
(D) Fe2(CO3)3 (2.0 g)
1).Which of the following statements about a sample of N2 in room temperature and pressure, is
wrong ?
Asagida verilenlerden hangisi 1 atm basincta ve oda sicakligindaki belli miktardaki N2 gazi icin
yanlistir .
(A) All of the N2 molecules do not have the same kinetic energy.
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 13
Butun nitrogen molekulleri farkli kinetik enerjiye sahiptir
(B) The molecules collide elastically with the container’s walls.
Molekuller kabin duvarina elastik olarak carparlar
(C) The mean potential energy of molecules does not change over time.
Zamanla molekullerin ortalama potansiyel enerjileri degismez
(D)If we double the absolute temperature, the mean speed of molecules doubles
Eger mutlak sicakligi iki katina cikartirsak , molekullerin ortalama hizlari iki katina cikar .
20)The rate of which of the elementary reactions below, would increase more if the pressure rises by
reducing the volume of the container? All reactions take place in the gas phase.
Asagida verilen tek basamakli reaksiyonlardan hangisnin hacmi azaltilarak basincinin
arttirilmasiyla reaksiyonun hizi artar. Butun maddeler gaz fazindadir.
(A) H + Cl2 HCl + Cl
(B) Br2 2Br
(C) 2H + H+ H3+
(D) Br + H2 HBr + H
21-According to the following figures, a cow uses plant leaves as a nutrition source. As we know,
the energy of sunlight is absorbed by plant leaves (Photosynthesis process). So, calculate the
percentage of the sun's light energy assimilated by a cow.
Asagidaki resime gore inekler bitki yapraklari ile beslenirler.biz biliyoruz ki bitkiler enerjini
gunesden gelen gunes isigini emerek depoluyorlar,(fotosentez yoluyla).buna gore asagidaki resmi
dikkate alarak inegin en kadar gunes enerjisi assimlediginin(depoladigi,vucudunda
tutdugu,benimsedigi) faizini hesaplayin.
a- 2%
b- 0.2%
c- 4%
d- 5%
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 14
22-The Karyotype shown below belongs to a …….
a- normal woman
b- normal man
c- woman with Trisomy 18
d- man with Trisomy 18
.
Resimde gosterilen Karyotip ………….. aiddir.
a- normal kadin
b- normal erkek
c-Trisomi 18 li kadin
d-Trisomi 18 li erkek
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 15
23-A musician suffering a stroke has lost his coordination and accuracy in playing piano. Which
part of his brain may be damaged?
Felce ugramis muzisyen piano calarken kordinasyon ve ayarlama problemi yasiyor.Buna
gore beyinin hangi kismi hasarlanmis olabilir?
a- Cerebellum(serebellum)
b- Medulla oblongata(medulla oblganta)
c- Hypothalamus(hipotalamus)
d- Limbic system(limbik sistem)
24-There is a receptor on the antennae of the male silkworm moth that plays a role in the
recognition of a female silkworm moth at a distance. What type of the following receptor is it?
ipek boceginin anteninde bir tane reseptor vardir ve bu reseptor ile uzaktaki disiyi tanir.bu
reseptor cesidi asagidakilardan hangisidir?
a) Photoreceptor(isik reseptorleri ve ya fotoreseptor)
b) Thermoreceptor(isi reseptorleri ve ya termoreseptor)
c) Chemoreceptor(kemoreseptor)
d) Mecanoreceptor(mekanik reseptor)
25-The diagrams show vertical sections of kidneys of a freshwater seal, Northern Three-toed
Jerboa (a species of rodent living in arid deserts of Northeastern Iran) and Persian fallow deer
(a rare ruminant mammal inhabiting in Khuzestan, Southern Iran, and in Mazandaran, Northern
Iran, and in an island in Lake Urmia in Northwestern Iran), showing the relative size of cortex
and medulla. Which kidney belongs to which animal? Assume that the majority of Henle loops
are located in the medulla.
Asagida gosterilen resimler uc farkli hayvanin bobrek kesitine aitdir.bu hayvanlar temiz su
hayvani olan seal(fok baligi) hayvanina,Jerboa hayvanina(col sicani) ve Persian fallow
deer(iran yoz geyigine)aitdir.resimde
medulla ve korteksin alani
gosterilmisdir.buna gore hangi bobrek hangi
hayvana aitdir?Henle kulpu medullada
yerlesir bunu da goz onunde bulundurun.
a. 1:Persian fallow deer 2: Seal 3: Jerboa
b. 1: Jerboa 2: Persian fallow deer 3: Seal
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 16
c. 1: Jerboa 2: Seal 3: Persian fallow Deer
d. 1: Persian fallow deer 2: Jerboa 3: Seal
26-Which teeth patterns belong to carnivores and which ones to herbivores?
(Asagidaki dis ornekleri karnivor ve herbivor hayvanlara aitdir.hangi resimler karbivorlara
hangileri herbivorlara aitdir?)
a. 1 and 2: carnivores(1 ve 2 karnivorlar)
3 and 4: herbivores(3 ve 4 herbivorlar)
b. 1 and 3: carnivores(1 ve 3 karnivorlar)
2 and 4: herbivores(2 ve 4 herbivorlar)
c. 1 and 2: herbivores(1 ve 2 herbivorlar)
3 and 4: carnivores(3 v3 4 karnivorlar)
d. 1 and 3: herbivores(1 ve 3 herbivorlar)
2 and 4: carnivores(2 ve 4 karnivorlar)
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 17
27-According to the figure below, which pair is closer evolutionarily to each other?
asagida tesvir edilmis evrimsel semaya gore ;asagdakilardan hangisi evrimsel akrabalik
bakimindan ve ya evrimsel surec bakimindan bir birine daha yakindir?)
a- Crocodile-bird(timsah - kus)
b- Crocodile-lizard(timsah - kertenkele)
c- Mammal-bird(memeliler - kus)
d- Lizard-bird(kertenkele - kus)
28-Which one shows the ascending order in the relative lengths of the caecum to the whole
alimentary canal of the following animals?
Asagidakilardan hangisi hayvanlarda bulunan kor bagirsagin uzunlugunu kucukten buyuge
dogru olan dogru siralamasidir?
a) Rabbits dogshumans(tavsanlar –kopekler-insanlar)
b) Rabbitshumansdogs(tavsanlar-insanlar-kopekler)
c) Dogshumansrabbits(kopekler-insanlar-tavsanlar)
d) Humansrabbitsdogs(insanlar-tavsanlar-kopekler)
1-
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 18
29-There are many migrating birds which go across the Iranian Plateau during the migration
season. Which of the following factors is the most effective in triggering their migration?
goc mevsiminde iran platosuna goc eden bir cok gocmen kus vardir.asagdakilardan hangisi
bunlari goc etmeye tetikleyen sebebtir?
a) Change in temperature(sicaklik deyisimi)
b) Change in food available(yiyecek varliginin deyisimi)
c) Change in behavior of predators(avcilarin davransi degisimi)
d) Change in daylight time(gun uzunlugunun degisimi)
30-A precipitation resulted from blood sample and antibody A. Which one of the following
choices is definitely incorrect?
Kan ornegindeki yogunlasma antikor A sebebi ile olmusdur.Buna gore asagidakilardan
hangisi kesinlikle yanlisdir?
a) Only gives blood to anybody with blood group B.
a)Her kes sadece AB grupu olanlara kan verebilir
b) Cannot take blood from anybody with blood group AB.
b)AB kan grubundan hic kimse kan alamaz
c) Can give blood to anybody with blood group A.
c)A kan grubu her kese kan vere bilir.
d) Can take blood from anybody with blood group O.
d)O kan grubu her kesden kan alabilir
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 19
Multiple Choice
Competition, 9th IJSO,
Tehran, I.R.of Iran
December 3rd , 2012
T – 20