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lndiqn Associqtion of Physics Teqchers

unapn FxaMlN IOR SCIENCE 2OL3-24L4NATIONAL STANDARD .EXAMINATION IN JUNI

Date of Examination 24th November 2013

Time: 15.fr) to 17.00 Hrs

INSTRUCTIONS TO CANDIDATES

ontheanswersheet , f i | |upa | l theent r iescare fu | |y in thespaceprov ided,oNLY|NBLocKCAPITALS.Useon|yBIUEor -B[ACKBALL pEN for making entries and marking answers. Incomplete'/ incorrea lcarelessly filled information may disqualify your

candidature.

write the Q, P. Code No. mentioned above on YouR answer sheet (in the space provided)' othenrvise Your answer sheet will

NOT be valued.

The question paper has 80 muhiple choice questions- Each question has 4 oplions' out of which only one is correct' choose the

correct answer and shade the oval in the coriespgnding box on the.answer sheet as shown below:

' Correct Method

O O O OA c o r r e c t a n s w e r c a r r i e s 3 m a r k s a n d l m a r k w i | | b e d e d u c t e d f o r e a c h w r o n g a n s w e r s ' -

A | | roughworkmaybedoneontheb |anksheetprov idedat theendof thequest i r rnpaper .

PtIAsEDoNoTMAnEAT\YIaREShTHERTEANSHADII]GtN:fHEsPAcEPRr,Z',DEDoNTHEA|tswERsHEEI.Arrswersheets are evaluated with the help of a machine. Due to thb, CHANGE OF EftlTRY ls HoT AIIOWED'

scratching or ovenrrrriting may result in wrong score. DO NOT WRITE ANYTHING ON THEBACKOFA'IISTA'ERSH€ET'

Use.of a nonprogrammable calculator is allowed'

The answers / sol,tiom to this question paper will be available on our website - www.iapt.ort.in by 3oth Norrcmbe r 2o13'

CERTIFICATES & AWARDS

Certficates to top 1o96 students of each.centre'

Merit certificates to statewise Top 1% students'

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Resuh sheets and the .centre top to/{ certificates of NSEJS are dispatched to the Professor in charge of the centre' You will

get your marks from the Professor in charge of your centre by January 2o14 end'

30o (or so) students are selected for the next examination - Indian National Junior science olympiads (lNJSo)' Individual letters

are sent to these students ONLY'

12. No querries will be entertained in this regard'

Please read the instruction carefully before answerirlg

5t4

lndian Associotion of Physics TeochersNATIONAL STANDARD EXAMINATION IN JUNIOR SCIENCE 2OL3-20T4

Total time: 120 minutes Marks:2210Only one out of four options is correct

1) One side of a glass slab is silvered as shown in the figure. A ray of

l ight is incident on the other side at angle of incidence i = 45o .

Refractive index of glass is given asl.5. The deviation of the ray of

l ight from its init ial path when it comes out of the slab is {Given

, . 6sin-' '=- = 23";

J

(") s" (b) 180' (c) lzo"

2) The number 5J41lies betweena) 29 and 30 b) 30 and 31 c) 31 and 32

{d1 +s"1

d) 32 and 33

3) Oxidation number and co-ordination number of ft in cisplatin etClr1run.1, are respectivelya) +4and2 b) +2 and 4 c)Oand 4 d)+2 and G

P€ssage for Q(tl-5): In a field one summer's day a Grasshopper was hopping about, chirping andsinging to its heart's content. An Ant passed by, bearing along with great toil an ear of pea hewas taking to the nest. "Why not come and chat with me," said the Grasshopper,,"instead oftoiling and moiling in that way?" "l am helping to lay up food for the winter," said the Ant, "andrecommend you to do the same." "Whr7 bother about winter?" said the Grasshopper; "Wehave got plenty of food at present." But the Ant went on its way and continued its toil. Whenthe winter came the Grasshopper had no food and found itself dying of hunger - while it sawthe ants distributing every day corn and grain from the stores they had collected in thesummer. Then the Grasshopper knew: lt is best to prepare for days of need

4l ln the passage given above there seems to be a factual error with respect to the antcarrying the food to the nest. The most probable reason for this mistake would be

a ) Pea pod is too heavy for an ant to carry to its nest.b) Pea cannot be carr ied by an ant in the summer because i t is a Rabi crop.c) Ant couldn't have passed by easily since it is the favourite food glgrasshoppers.d) Grasshoppers avoid coming out in summer and thus there cannot be

grasshopper in the story.

II

5 1 4

5) what could be the most plausible rea.son that arf the ants that toited and moired in the' summer were happy and content in *re winie;

" qrIrr LrrdL rolleo and moilr

;i ffI I"T::??:j:[iffi:since their rood was not shared with Grasshopper.c) Ants were happv,in." t'"v ";,Jrffi;n

,|o?"l;:,-t;'"1lll,,'::'o) *:::

[Tff:ured was efficienuy o,,i,iuu-,"""J;;; '#;"1',o,n",

",,,n"6) Grasshopper was at fault in this story mostly because

a) Of its attitude towards ants who were working tirelessfyb) of not having a forethougni io ,to." food for the upcoming winter season.c) of chirping and singing tJitsieart's content in the summer.d) ft shourd have askj ;;;;; tn" rooa "nJ

;;;; to surpass the wintersomehow.

7 ) A n o b j e c t o f m a s s 1 k g i s m a d e t o s l i d e d o w n a s m o o t h i n c r i n e d p l a n e o f r e n g t h 2 o n t l f t h ekinetic energy possessed by the body at the bottom of the plane is 100-r , then the inclination ofthe plane with the horizontat is (take g=10ms-2)

8) Two circles each of radius 3 touch each other externaily in the prane. In how many ways can acircfe of radius 8 be ptaced in the prane touching each of these two circles?a ) 2 q 4 c ) s d ) 89) Which of these elements has the greatest electronegativity?a) Br b) N c)o

(a) ls' (b) :z' (c) oo'

10) An inclined plane of incrination g is praced in water asshown in figure given below. Consider a small area(44) around point p at a depth h. lf Density of water is. _ - ' ' - . . :p and accelei,ation due to gravity is g the forceexperienced bydA due to hydrostatic pressure is

(d) ro'

d ) s

IiI,f

a) peh(AA) b) pgh(AA)sin0 c)pgh(ae)cose d) pgh(AA)sec0

tu 'TA:rt

- t' # + y -5' 4x + 2yare the sides of an equirateral triangrg its area is crosest to thea ) 8 4 r . b) 8s c) s6 d) 87

514

12) The pH of a 0.025 M solution of KOH isa) 1.50 b) 3.5s c) 10.31 dl12.40

13) consider the following two statements about l ight &sound. choose the most appropriate option(i) When light and sound travel from air to water, l ight may bend towards normal while sound

may bend away from normal.(i i) Sound is longitudinalwave while l ight is transverse wave.

a) Statement (i) is correct while statement (i i) is incorrectb) Statement (i) and statement (i i) are both correct and statement (i i) is not the reason for

statement (i)c) Statement (i) and statement (i i) are incorrectd) statement (i) and statement (i i) are correct and Statement (i i) is the correct reason for

statement (i)

14) lf xf =q3, y/=b3 ond zl = c3 then I equalsr 4

. 0c 'a) --;-

a -

. . 0 ' cD) --;

a'

r ) A

c ) + d )u

a0 '---;-

I

.I

i

15) How many H atoms are in 3.4 g of C12H22O11?a) 6.Ox1023 b) 1.3x104 c) 3.8x1022 d)6.0x1021

Passage Q {16-18): Diatoms are the most common photosynthetic aquatic microorganismsgroup of algae which are unicel lular and can exist as colonies in the shape of f i laments orribbons, fans, zigzags or stars depending on the quality of the water. Diatom communitiesare a popular tool for studies of water qual i ty and pol lut ion management. Karthik fromBangalore recently went on a field trip from Bangalore to Mysore. on the way he stoppedhis car at a sewage canal, a lake and a mountain stream and collected water samples fromall of these places for his lab work. After a careful analysis of his water samples, he observedthat diatoms came with varying sizelshape and the size /shape increases has (have?)something to do with the water qual i ty.

1"6) Below are the diatoms observed under a microscope by Karthik. Help him to recognisethe correct order of sample local i t ies (Viz. , canal, stream and lake).

,;{r

i,r*$ ( n\ zz

ffiwR=\\-?ry*\ J:*1 +

514

a) A- Mountain stream, B_ Sewage Canal, C_ Lakeb) A- Sewage Canal, B_ Lake, C_ Mountain Strbamc) A- Lake, B- Mountain strearn, C_ Sewage CLAd) A- Mountain strearh, B-,Lake, C- Sewqge canal

17) what is the take home message from the above experiment

a) Diatoms come in different sizes and shaoesb) The difference in size and shapes from different water samples is

suggestive of the intensity of water pollution.c,l Karthik enioyed collecting samples from different locations

t d) Nothing can be inferred from the above experiment.

18) In the above experiment, difference in sizes and shapes of diatoms should be inferred asa) Different species of diatoms.b) Different genera of diatoms.c) Different families of diatoms.d) Different orders of diatoms.

19) The percentage change in acceleration due to gravity at an altitude equal to radius of earth, comparedtothatonthesurfaceofearth isgiven by

a) 25% increase blgso6 decrease c) 75%decrease d)zs%decrease

2o) Le tg ,bbetwopos i t i verea tnumberssuchtha t acb<! *a te t x=(o* ! l - {a+} ) . f t , "n

a) x is always greater than zero b) x is ahrays less than zeroQ x=O d) l*o such definite conclusion can be,drawn about x

21) which of the following species has standa;d enttralpy or torr"itn as o'kj mol{?a) HzOtrl . b) Nala c) Na6y d)CO4d

22) A particle accelerates wit-h a constant acceleration ae and reaches a maximum velocity and thendecelerates with a6 and comes to rest. The position time graph describing the situaiion ir;"r;represented byX inm

L75

oa

0.1'

tXinn

D'

lr5

E

a.R

*a

(a) (b)

514

al0.100 mol kg-1c) O.160 mol kg-1

Xin n

125

b) O.128 mol kg-ldl O.201molkg-l

lt:

c;;

0_:t

23) Let m be the number of distinct (non congruent) integer-sided triangles each with perimeter 15and n be the number of distinct (non congruent) integer sided triangles each with perimeter 16.Then m+l equals

al -2 b ) 0

(d)(e)

c ) 2 , d ) - 4

24) What is the molality of a solution made by dissolving 100 g of bromothymol blue {C27H2sBrzOsS)in 1-00 L of ethanol on a winte/s day at 1@C?'The densiry of ethanol at this temperature isO.7979kgLL.

25) Two bulbs of specifications 50W, 220V and a 100 W, 2mV are connected first (i) ln parallel and

.tlren tii) lry series across 220v power supply. choose the correct statement

' (a) ln (i) 50 W willglow brighter and in (ii) 1m W wiltglow brighter

(b) ln (i) Sb W wilt gtow brighter and (ii) both wiil gtow equaily brighter.

(c) ln (i) 100 w wilt glow brighter and (ii) So w witt gtow brfiter

(d) ln both cases the 50 W bulb willglow brightef. \

26) Let I be the number of 4- digit integers, each:ending in 3 (in units placej and each divisible by11. Then

a l 7 O < T < 7 9 b ) S O < r < 3 9 c ) 9 0 < T < 9 i d) r> 1oo

27) 1.00OmL of 0.1000 mol L-1 hydrochtoric acid was diluted to 100.0 mL with deionised water.10.o0 mL of this solution was diluted to 100.0 mL again using deionised water. What is the,pH ofthe f inalsolut ion?

{

a) 2 b ) 3 c ) 4 dls

5 1 4

2s) While playing football, Dimple fell down and was badly wounded oh her left ankie. The Doctorprescribed her antibiotics for a week which should have healed her of the wound in a week.However, Dimple's wound did not heal in a week. What among the following could have beenthe reason for inability of the wound to heal in the prescribed time frame given by the doctor?' a) Prescribed medicine's date was expired.

b) Dimple wouldn't.have taken the full course of the antibiotics.- c) Both a & b could be the reason '

d) Docto/s inability to prescribe the correct medicine for the wound.

29) Which of the following situation is impossible?a) A body having velocity and acceleration in opposite directions.b) A body having zero velocity and non zero acceleration.c) A body having constant acceleration and variable velocity.d) A body having constantvelocity and variable acceleratioh.

30) At what time (to the nearest second) immediately after 4 o'clock will angle between the handsof the clock be the same as that at 4 O, clock?

a) 4n42'so' b) 4h 43'39' c) 4h 43'4d d) sh 5'27'

3t) 0.5755 g of a compound, containing sulfur and fluorine only, has a volume of 255.0 mL at2SS.0 K and 50.01 kPa. What is the molecular formula of this compound?a) SzFz b) sF2 c) SF4 d) sF6

32)Given here is a phylogenetic tree (family tree) ofgreater apes. Which of the following statementscannot be true from the tree? {mya- millionyears ago)

a). Humans did not evolve from chimpanzees.b) Humans and chimpanzees are evolutionary cousins.c) Orangutans evolved much earlier than Humans.d) Humairs are highly evofu-ed among great apes.

33)A tiquid (A) of density 1.6gcm-3 and liquid (B) of unknown density ispoured into a U-tube as shown in'the figure. The liquids are immiscible. lfheight of A is ha= 26.6cm and height of I is hs=50 cm the density of g is ia) 0.85 g cm-3 b) 3.01 g cm-3 tt"

Ic) 0.33 g cm-3 d)1.18 g cm-3 +

34) lf o and b are two positive real numbers such that = 6 , then a positive value of f,

rct

between' a ) 2 a n d 3

a2 +b2

ab

b ) 3 a n d 4 c ) 4 a n d 5 d ) 5 a n d 6

i l

II

i

514

"' lH:hT;:rl# * exists betwee n cH3cHcr2 a nd cH2cf cH2cr is

c) positionaf isomerism I) functionalgroup isomerism- d) metamerism36) The term Biodiversity refers to

. a)Species Diversityc) Ecosystem diversity

37) Diagram shows trajectory of a cricket bail.the acceleration of ball at points p andQ respectively is( a ) l + ( b ) | |- | |

' - | |+ l + +

b) Genetic diversityd) Alf of the above

The set.of arrows which show the direction of

( q / \ H I / \

38) Sucharitha purchases x pencils at Rs x eaclsHe purchases aftogether 5o *cm" .^" --.:t^f "::^1Rs

y each and z notebooks at Rs z each.;nil:._,Ts

af togeth e r 50 items . "o ; ;, ;. ; ;:. ;"":H:1 ; ;:_1,:: :: ffi Xnotebooks is

I

39) The metal that does n^r oirra rJ ^- ^_a)

€es not give H2ll, ,*"Tl"l, with dirute HCr isc)Ac d) ca4oJ on a field trip in

loTl America, students_no.ticed that when threatened, Horned rizards (Genus:Phryiosoma) squirt uooo "t

tti ati;;"rt when the o-r"r*. asked what courd have been thereason behind such behaviout or go.n"l lizards,

";;;"d"";1",0 an", certain sensory receptorshad fired and triggered a n""on"l-'"n"".urrin"ting inln.r"oing the pressure in their sinus,Tj[:":i::*:tiitlT::i:#r#il',,.#:""',,'l;I]'on*r,",studentsaidthatitwasa) The first response is correct, wrriie ttr" second is incorrect.b) Both expranations are .".;;;',;d can be scientificary tested.c) The first response is biotogicaf *i,1" ,n" second is phifosophical.d) The first expranation it ,"J"or"

", a scientific t vpoir,,"rl, ,ihire the second is not.

41)t f temperatureofacertainmassofaruminunihavingspecif icheatcapacityof0.g

l /gocislowered by ooc and heat rost is g6J, ttren mass of afuminum isa) 169 b) 48g '

. t .og d) 2ost'

HIfl; il:;',i*;:,: ror which the cubic equation r - aat + 3ax - o = ,has arr rear

a ) o O ) r c ) 2 d ) 3

IIiirlflt ir l

tiI

II

st4

43) The maximum number of isomers for an arkene with morecurar formuta coH. is? ) s b ) 4 q 2 d ) 3

44) People residing. in ::: ':"1

area usually do not face the problem of Thyroxin hormone deficienry' because their food intake,wiil be rich in one of the foilowing minerars.a) Sodium b)Chlorine c) lodine d) phosphorus

45)'ln photoelectric effect, the maximum kinetic energy (Er) of photoelectrons depends onfrequency (f) of right incident on a metar surface of work runction ioj. i" "" ""pieriment /

isvaried and E* is measured. To determine value for pranck,s constant (h)(a) Plot Eeagainst g and find intercept of best fitted line.(b) plot fsagainst/ and find slope of line of best fit.(c) plot Elagainst cp and find slope of line of best fit.(d) plot Esagainst/and find intercept of best fitted line.

46) Around a lawn which is of semicircular shape a pavement of uniform width is laid. lf the ratio ofthe aiea of the lawn to the area of the pavem;,lr;;;;,;n"" ,t" ratio of the outer and innerperimeters of the pavement is , t"s'

d)+246

47) The method that cannot be used for removing permanent hardness of water isa) adding sodium carbonate b) distillationc) adding caustic soda d)-boiting

48) In angiosperm pfants, companion cell is associated with which one of the foflowing elements?a) Sieve tube b) Tracheids c)Vessels d) Xylem fibre

49) Essential requirement for the operation of a step down transformer is(a) Laminated iron core(b) Electricar connection between primary and secondary coirs.(c) Magnetic interaction between primary and secondary coirs(d) Non magnetic core.

50) Let ABC be a triangle in which AB = AC. Let D be a point on AC such that BD bisects angle g.Vafue of the ratio 48 '_ ts between

a r ;b ) :J

4 :c

a) 1.0 and 1.5 b)1.5 and 2.0 c) 2.O and 2.5 d) 2.5 and 3.0

51) consider the following reaction: a Pclr(g) -> Pok) + e cllg). rf the initiar concentration of pcrr(g)is'1'0 M' and "x!' is the equil ibrium concentration of Pe(g), what is the correct equil ibriumrelation?a) K. = 6x7c) c= (x)(ox 1611r.o- +x14 lif =

'.:'/;t: .;)^

l 0

sL4

52) In pregnantwomen, foetus's physiological functions l ike nourishment, respiration and excretionare taken up by

a) Stornach of motherc)Umbil icalcord

- c )2 .1 km

b) Placentad) Uterus .

53) On a rainy wet day, a thunder is heard 5 second after l ightening. lf speed of sound is 35oms-1 thealtitude of the clouds isa) 1.8 km b) 1.9 km d ) 2 . 5 k m

54) A certain principal becomes Rs. 95800/= in 2 years if compounded annually at a certain rate ofinterest. The same principal becomes Rs.9724A/= in two years if compounded half yearly at thesame rate of interest. The rate of interest is

c| 10/o

55) Which properties of plastics make their dispo5aldiff icult: ( l) PVc produces harmful combustionproducts; (l l) polyalkenes are highly.flamrnable; (l l l) polyalkenes are non-biodegradablea) | and l l only b) | and i lt only c) i l and i lt only d)t, lt, i l t

56) Suresh accidentally touched silencer of his two wheeler while parking and withdrew his legimmediately. ldentifu the correct order of the flow of message to the brain?a) Receptor )Sensory heuron)CNS)Motor neuron)Effectorsb) Sensory neuron)CNS)Motor neuron)Effectors)Receptorsc) CNS) Motor neuron)Effectors)Receptors)Sensory neurond) EffectorsiReceptors)Sensory neuron)Motor neuron

57) There are three bodies A, B ond C.Body A when brought closer to B, attract. When body I isbrought closer to Cthey repel. We can then concludea) Body A and 8 should have opposite charges while Body C should have the same charge as Ib) Body I and 6should have same kind of charge while BodyA may.have opposite charge.

:l BodyA and 8 should have same charge while Body cmay have opposite charge.

d) Body c is neutralwhire Body A and 8 should have opposite charge.

58) A pen costs Rs L3/= and a note book costs Rs. 35/=. Let rn be the maximum number of itemsthat can be bought for Rs 1000/= and n be the minimum number of items that can be bought forthe same amount. Then m + n is

, a ) 7 6 b) 88 c) 96 d) s8

59) When the pH of the environment of a protein is changed, it is said to be denatured. This is dueto:

a) 8% \

ut Slz3

a) breakage of peptide bondsc) loss of tertiary structure

b) breakage of disulfide l inksd) breakdown of R groups

d) L2 ' /z%

60) lf Brain is controll ing unit of an organism, then at cellular level which cell organelle can becomparable to Brain?a) Chloroplast " b) Ribosome

I I

c) Nucleus d) Lysosome

5 1 4

51) Aldebaron, the brightest star in the constellation Taurus rises at local t ime 7:00 pm on 1'tofOctober. On November 1" the star wil l r ise ata) 5:00 pm b) G:00 pm c) 9:00 pm d) 8;34 pm

62) In thexy-p lane letA be the point (5,0) andt bethe l ine y: i . * " numberof pointspon the

line L such that triangle OAp is isosceles is (O being the origin)a) 1 b) 2 tt s d) infinitety many

63) For the reaction, 2A + B -+ C which relationship is correct?a )a lA l= a l c l b ) -A lA l = A l c lc) -2AlAl= Alc l d)-AIAI =.2alc l

64) In some societies, "Women were solely held responsible for giving birth to female baby,,-assuming no role for men. But scientif ic advancement has proved men equally responsible forthe birth of either sex. Armed with this information which of the following would be the mostappropriate scenario for the birth of female child?

a) ovum with X chromosome and sperm with y chromosome is FEMALEb) Ovum with Y chromosome and Sferrn with y chromosome is MALEc) ovum with X chromosome and sperm with X chromosome is FEMALEd) ovum with X chromosome and Sperm without chromosome is FEMALE

65) A block of rilass 2 Kg placed on a floor experiences an externat force in horizontal direction of20N, frictional force of 6N and normal f6rce of 20N. The body travels a distance of 10m underthe combined effect of allthese force. tf Initially body is at rest then what is the kinetic energy ofthe body at the end of4ma) L4oJ b) 260J c) 60J d) 4G0J

55) ff ,t'= a + 7 and x + (b/x)--a; then xequals

^ , a ( b + 1 ) . , a b + ' l , a b + a + 1 . . . a b - a - 1a, --# b) __;_: c) =___ --____: d)

--- =

--'

a ' - b a 2 - b - '

a z _ . b a 2 _ b

57) An electrochemical cell constructed for the reaction: Cuz*("ql + MGt -) Cu1,t+ M2t"ot has an Eo=O.75 V. The standard reduction potential for Cu2'1"qy is 0.34 V. What is the standard reductionpotential for M2*1"01?

a) 1.09 V b) 0.410 V c) -0.410 V d) -1.0s V

68) Which one of the following is said to produce seeds exposed and they are called naked seedplant

a)Deodar & pinus b) Marsilea & Nostocc) Maize & Garden pea plant d) Spirogyra & Funaria

59) A body of mass 2 kg moving in the positive X-direction with a speed 4ms-1 coll ides head on withan another body of mass 3kg moving in the negative X-direction with a speed of 1ms-1. Duringcoll ision a loud sound is heard and they both start moving together. The sound energy cannotbe greater thana) L2J b) 14J c)15J d)17.sJ

t2

514

7O) Let a, b, c be positive real numbers such that abe l, (obf = pcf = (caf = s6".Then x equalsa ) 1 b ) 2 c ) s d ) 4

71) Which radiation is the easiest to shield?a) alpha b) beta

a) SO32- b)co32- c) Nog d)so3

c) gamma d) neuFon

I

72) ldentify the correct order of sequence from exterior to interior.a) Cell)Nucleus)Chromosome)DNA)protein

, b) Nucleus?Cell)Chromosome)DNA)proteinc) Cell) Nucleus)DNA)Chromosome)proteind) Cell)Nucleus)protein)DNA)Chromosome

73) In nuclear reactor, the electrron3 and protons are moving in opposite direction across a smalthote in 2 second' lf number of electron and protons "rix#i ""ch

, the cu*6nt through thehole is given bya) 1.5 rnA b) OmA c) G.4mA d) 3.2mA

7 4 ) r h e s u m t - 1 * 1 - 1 - . 1 - 1 * 1 1 ,- 2' 3 t-5 " ' -

2 ' . ' .*zOf, equals

- \ 1 1 1 1a l _ + _ t - f l

1006 1 ,W7 '1008 '

1 1 1 .b)' rca7 1oo8'1009 -6i5

- 1 1 1 - 1 1: .1006 7007

' 1008

' """'-'..:-.-m.

d ) 1 * 1 * 1 * 1 1' 7007

' 1oo8

' 10@ -m.

.75) Which species below has the same general shape as NH3?

75) After hearing to an influential lecture o4 "hpw to conserve environment by avoiding usage ofplastic"? Ghan Shyam resolved that he shouliJ also contribute towards protecting theenvironment from plastic menace. can you suggest him the first step how ,ioulj r,"-co "ooradoing this efkctively

a) He shourd urge his parents to stop using prastic materiars at home.b) He should write a letter to the lodal civic body againsr ;;tG ot;; materiats aroundhis locality.c) He should practice minimising plastic usage hiinself.d) He should ask his teacher to advice people on his behalf to stop usage of plastics.

l 3

: --i-i]

Column 1 Column 2

f) fne point P is at the midpoint of the twoconductors carryingcurrent in same direction. t, ',,

P) 82>81; Thus 82 + 81 getting lnto me plane or

the paper.

2l The point P is on rightside of secondconductor carryingcurrent in samedirection t { .Q)'Bz>B; Bz - Br comlng our oI tne Prdl

the paPer.

8 2 - 8 1 = QRl Bt= -gr t1 fne Point P is at the

mid point of the twoconductors carryingcurient in oPPositedirection. t,.,

S) B"=BtTtrs Bt.Bz = 2Bgettinginto the

plane of paPert -

4) The Point P is at theright of the twoconductors carryingcurrent in oPPositedirection

t, ,l o

514

ire placed parallel to each other' They carry current 11 and 12 (lz = lr)' The

magnetic flelo is e1 aii 82 respectively. Different situation are given in column 1' The comments

on the direction and strei4h of magnetic field are given in column ll' Match the following

baseofaconeisdo'ubledthenthes|antareabecomes3timestheorigina|7s) lf theradiusof thebaseof a::::,:t-*lT a&upred(that'isincreasedto4

, slantlarei. Suppose when the radius cffthe base of the cone is qr;

.times), the slant area becomes k times the original slant area' Then the integer closest ts * is

a) 5 b )g

1ii l

t lt l

lltt

79) The mass of O.2 mole of Oxygen molecule is

a) 5.4e b) 3'2C

80) Wuchereria is an examPle oft

") ArthroPoda b) Annelida

dl2.7se

d)Nematoda

l4

c) Arthropoda