I Series SSO I Code N~. '55/1a;)s ;r.

Roll No.fB-;t.

Candidates must write the Code on

the title page of the answer-book.

rRTamn <ffis em 3'fR-:f~<P1 ij) ~-TO~~~I

• Please check that this question paper contains 15 printed pages.

• Code number given on the right hand side of the question paper should bewritten on the title page of the answer-book by the candidate.

• Please check that this question paper contains 30 questions.

• Please write down the Serial Number of the question beforeattempting it.

• 15 minutes time has been allotted to read this question paper. The questionpaper will be distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., thestudent will read the question paper only and will not write any answer onthe answer script during this period.

• ~ ~ Cfi\ #f fen ~ ~-'tr-f if ~ ~ 15 ~ I

• ~-tr-f if ~ ~ cnl 3W ~ ~ its ~ cir ~ ~-~~ctll ~ lJ:9-~ 11\ft;r@ '1

• ~ ~ Cfi\ #f fen ~ ~-tr-f if 30 ~ ~ I

• ~ ~ qrr ~ ~0(9"11. ~ ~ ~ ~, ~ qrr ~ ~ WRi

• ~ ~-tr-f cir ~ ~ ~ 15 1lRc:~ ~ ~11"f71T ~ I ~-tr-f ~ ~ ~ if

10.15 ~ fcn<.rr ~ I 10.15 ~ it 10.30 ~ CfCI) ~ m ~-tr-f cir ~ ~

~ :wff~ ~ ~ ~ ~-~ 11\ cnW ~ ~ ~ I

PHYSICS (Theory)

~fdS1I~(~)

Time allowed : 3 hours

5511 1

Maximum Marks : 70

p.T.a.

---~---

General Instructions :

)

(i)

(ii)

(iii)

(iv)

(v)

All questions are compulsory.

There are 30 questions in total. Questions 1 to 8 carry one markeach, questions 9 to 18 carry two marks each, questions 19 to 27carry three marks each and questions 28 to 30 carry five markseach.

There is no overall choice. However, an internal choice has beenprovided in one question of two marks, one question of three marksand all three questions of five marks _each. You have to attemptonly one of the choices in such questions.

Use of calculators is not permitted.

You may use the following values of physical constants wherevernecessary:

c = 3 x 108 ms-1

h = 6·626 x 10- 34 Js

e = 1·602 x 10-19 C

1-10 = 4n x 10-7 T m A-I

1-- = 9 x 109 N m2 C-241tE

o

Mass of electron me = 9·1 x 10-31 kg

Mass of neutron mn == 1·675 x 10-27 kg

Boltzmann's constant k = 1·381 x 10-23 J K-l

Avogadro's number NA = 6·022 x 1023 / mol-1

Radius of earth = 6400 km~~:

(i) FJft JTR 3fRqpf ~. I

(ii) rf{- JTR-"C{;{ if !FfT 30 JTR ~ I J{8 1 it 8 if JRitq; ~ -~ 3fcF; ctT~) JTR9 -# 18 if JRitq; J{8 rfr 3fcF; CfiT~, ~ 19 -# 27 if JRitq; J{8 rft;r 3fcF; CfiT ~

(MT J{8 28 it 30 if JRitq; ~ rikt 3fcF; CfiT'~ I

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55/1 2

due to an electric dipole at an

(iv) J,~'lr:pc1c.<it ~ eft 3JT1Frr ';fjt. # I

(v) ~ 3ilC{~4q, it 3fTT! MJ..-ffC1Rstrl <JftFrrq;.H4rll'q,)" it 1fFif cnr ~. cp: ~

~ :c = 3 x 108 ms-1

h = 6·626 x 10-34 Js

e = 1·602 x 10-19 C

~o= 4n x 10-7T m A-I

. _1_ = 9 x 109 N m2 C-241tf

o

" ~ cn1 ~ me = 9·1 x 10-31 kg

~ cn1 ~ ~ == 1·675 x 10-27 kg

~ G~I1I--l H~dicf; k = 1·381 x 10-23 J K-l" ..

3-ilcll1llil cn1 ~ NA = 6·022 x 1023 / mol-1

"9:~ cn1 ~ = 6400 km

/ What is the electrostatic potentialequatorial point ? 1

Name the EM waves used for studying crystal structure of solids.

What is its frequency range?

irm cn1 ~~ctl~ ~ CfiT ~ ~ If ~ QFr crrffi ~-T.j~chl~ ~ CfiT

-;:m:r ~ I ~ 3Wlffi -qfuR CFIT ~ ?

1

~ An electron does not suffer any deflection while passing through a

region of uniform magnetic field. What is the direction of the magneticfield? 1

~ ~~~I~ fctlffi l:I.cf;~I1I--l ~~cf;I~ ~ ~ ~ ~ ~ ~ ~ ;r@ ~ I

.... 'l .. ~ cn1 ~ CFIT~ ?

55/1 3 p.T.a.

(iv) ~M.'1?c1c< it 3TPi/1r eft arprFrr ~. ~ I

(v) ~ 3WH4Ch it 31fTl HJ-rffMRstd '4ffrrq,. h4diChl" it rrr;:ff w ~ cp: writ

8' :

due to an electric dipole at an

Name the EM waves used for studying crystal structure of solids.

What is its frequency range?

imT q,1 r~~c.1l~~ cnr ~ ~ if ~ ~ ~ ~--q~Chl~ GtrIT cnr

-;wr ~ I ~ 3W[fu -qfu:n: CFlT ~ ?

1

1

.~ An electron does not suffer any deflection while passing through a

region of uniform magnetic field. What is the direction of the magneticfield? 1

~ ~~~I..j fcnm ~Ch~+il.-j :i~Chl~ ~ ~ ~ it ~ ~ ~ ~ ~'I ~ q,1 Rm CFlT ~ ?

55/1 3 P.T.D.

4./, How would the angular separation of interference fringes in Young'sV double slit experiment change when the distan<fe between the slits andscreen is doubled ? 1

*r ~ ~ m if ~ (f~ ~ .~ ~ cn1 ~ coT ~ ~ 11\ ~rd~~UI ~

~ CfiTufr1 ~~ if cp;rr l{ R,qJ-i ~ ~ ?

~ Two thin lenses of power + 6 D and - 2 D are in contact. What is thefocal length of the combination ? 1

~ ~. 'ffi1, ~ ~ + 6 D (F.IT - 2 D~) ~ if W ~I ~~'Jlrj ~ ~

~ cp;rr ~ ?

J. The stopping potential in an experiment on photoelectric effect IS

1·5 V. What is the maximum kinetic energy of the photoelectronsemitted? 1

>rcfim-~ ~ ~ fcnBt m if f.:rUm fcNq 1·5 V ~ I 6ru~d >rcfim-S~q.c.I<1'icn1

31f~ ~ ~ cp;rr ~ ?

YTwO nuclei have mass numbers in the ratio 1 : 8. What is the ratio oftheir nuclear radii? 1

~ ~ cn1 5\~I1I-i ~a# CfiT ~ 1 : 8 ~ I ~ ~ ~3TI CfiT ~

C!<lT ~ ?

~GiVe the logic symbol of NOR gate. 1

9..

'P

55/1

Draw 3 equipotential surfaces corresponding to a field that uniformly

increases in magnitude but remains constant along Z-direction. How

are these surfaces different from that of a constant electric field alongZ-direction ?

~ ~ ~ dC\j~l{ cfR Wffcrqq ~ ~ ~ ~ if l:!,~~I1I-i ~ m-m ~,

~ Z-Rm ~ ~ frr«:r WCIT ~ I ~ ~ ~ ~ it ~ m N?f ~ -m fcnBt

frr«:r ~-a);r ~ Z-Rm ~ ~ ~? .

4

2

~efine electric flux. Write its S.1. unit.

A charge q is enclosed by a spherical surface of radius R. If theradius is reduced to half, how would the electric flux through thesurface change ? 2

~ 1:K1CR1 Chl"-qftW ~ I ~. S.I. ~.~ I

~ 3ifcm qOO R~ ~ ~ ~ -q ~ ~ I *~ coT 3TIm ~ m~, -ffi ~ it ~ ~ ~ 1:K1CR1 -q cp:rr \1KCldrJ ~ ?

Ilhefine refractive index of a transparent medium.V A ray of light passes through a triangular prism. Plot a graphshowing the variation of the angle of deviation with the angle ofincidence. 2

00 ~ ~ ~ 3-!\1C1drJictl Chl ~ ~

~ ~ fW1 00 ~ ~ ~ ~ ~ I ~ cnTur -q \1KClc1rJ ~ ~

~ cirur -q \1K CIJrJ coT ::rTLP ~ 'r~ctl,- ~ I

~alculate the current drawn from the battery in the given network.

j Rl = 1 Q .

+

4V

2

55/1 5 p.T.a.

~ ~ ~ if ~ ~ "ffi ~ ~ mu YKctlf""cQ ~

R5'= 2 Q

+

4V

~A~wer the following questions : .v4) Optical and radio telescopes are built on the ground while X-rayastronomy is possible only from . satellites orbiting the Earth.Why?

~- The small ozone layer on top of the stratosphere is crucial forhuman survival. Why?

'R f.1ftRf ~ ~ ~ ~ x-fcn\uT

.. r. Cfi\ W ~ '[ffi m -B'licf ~ t

(a) ...... ~ .. W-lT ~ ~ "'r~~-~ cpr ~"'r~ cpr

~?

(b) ~~dIY~SC1~. ~ -00: 'R itit-m ~ "%i l1RCf ~ ~ ft;m: r r

~lcpIT?

Define current sensitivity and voltage sensitivity of a galvanometer.

Increasing the current sensitivity may not necessarUy increase thevoltage sensitivity of a galvanometer. Justify.

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fcnm ~rl-il~,{k\cn1 mu ~j.jlrc:dl if ~ ~ 'R ~ 3'lIq~~ctl' ~ ~. 1% ~ ~

r if .~ ~ it I ~ ~ ~ I

55/1 6

G Define the term 'linearly polarised light' ..When· does the intensity of transmitted light become maximum, whena polaroid sheet is rotated between two crossed polaroids ? 2

'k__ ~ wmr' Ch1~ ~ I

~ ~ ~ YI~~I$s"i~ ~ if coW 3P1 YI~~I$Sm c€t ~ ~ t m .",,,r.,~wmrCh1~~~iRrr~ ?

YA wire of 15 Q resistance is gradually stretched to double its originallength. It is then cut into two equal parts. These parts are then

connected in parallel across a 3·0 volt battery. Find the current drawn

from the battery. 2

fctm ClR, ~ m~15 Q~, c€t ~-~ ~ 1:R ~ ~ 31CRr ~ ~

Chl~~~% l~m~~wITifCfiTGT~~ I ~·'lWITc€tm

3·0 ~ Ch1~ ~ fuit it YI~cf~~ if ~~r\Jjd ~ ~ ~ I ~ it "ffi 7f{ ~

mu~~1

17·01 The mass of a nucleus in its ground state is always less than thetotal mass of its constituents - neutrons and protons. Explain.

Plot a graph showing the variation of potential energy of a pair ofnucleons as a function of their separation. 2

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Ci2IT >TtiRf - ~ ¥1 >\CX1~lri it Cf)11 ~ ~ I ~ ~ I

(b) ~fl .~ ~ Ch1~ ~ if yR-~Jric€t ~fl ~ l2~ ~ ~

~~if~~~mcn~1

18. Write the function of (i) Transducer and (ii) Repeater in the context ofcommunication system. 2

OR

'firite two factors justifying the need of modulation for transmissionof a signal. 2

55/1 7 p.T.a.

~~ ~*~it (i) ~1"'*iS~<i~H~ (ii) ~oi'!.IqJC:P ~ CfiT<f ~ I

.~

M fur;:ffi ~ ~ ~ ~ ~ ~ ~lq~~c:pC11 00- ~ ~ CflRCP ~ ~-.:>

~ '1"fu" ~ I-.:>

19. A positive point charge (+ q) is kept in the vicinity of an uncharged

conducting plate. Sketch electric field lines originating from the point

on to tl-z ,·,u.rfaceof the plate.

Derive the expression for the electric field at the surface of a chargedconductor.

OR

~a.rallel plate capacitor is charged by a battery. After some time thebattery is disconnected. and a dielectric slab of dielectric constant K is

inserted between the plates. How would Wthe capacitance,'-fii1-the

electric field between the plates and .(.iii)the energy stored in the

capacitor, be affected ? Justify your answer.

cnW ~ ~ ~ (+q)M3i-iI~r~lC1 ~ ~ ~ ~ ~ ~ ~ I ~

~. -B ~ ~ ~ ~ ~.1R ~ qrffi ~-~~ ~

~~~~~1R~~~fW1:~~~

fcIttft "WlRR ~ "Bmrer ~ ~ IDU ~ ~ ~ ~ I ¥-9 w:r-r ~ ~

~ ~ Cfi\ WIT ~ ~ ~ cnW Y~J~~C1 11ft ~ Ll~I~~C1ic:p K ~, ~3tt ~

~ W ~ ~ ~ I (i)"Bmrer ~ mfurr, (ii) ~ ~ ~3tt ~ ~ ~-~

(l~ (iii) ~ it ~ ~, 1R q<IT >f'l1fcf ~ ? 6W ~ ~ ~ I

55/1 8

B

R

A

.State the principle of working of a meter bridg¢.

In a meter bridge balance point is found at a distance II withresistances Rand S as shown in the figure.

X,/I./VVVV't., ,, ., ., ,

t • _ •••••

LCi)(ii)

+,1- (

When an unknown resistance X is connected in parallel with theresistance S, the balance point shifts to a distance l2' Find theexpression for X in terms of ll' l2 and S. 3

c{) A.;'" iiTI ,i<1>,4.""<:11 'lir r••.• ,«1 fufu!1I: Im( .~ ~ ~ if ~ ~ W-lfu,m if ~ ~, R ~ S ~ ~~ ~ II 1R ~ mm t I

R

Xf'NYVV", ., ., ., .

A B

+11- (

\ifq m~S ~ YI~ct9h~ if ~ ~ ~ X ~~~~ q)\ ~ ~ t m

~ Wo ft.2lfu ~ l21R ~I'il •.d~~m ~ t I 'X ~ ~ ll' l2 ~ S ~

~if~~~1

55/1 9 P.T.D.

cY~tate Faraday's law of electromagneticinduction.~ A jet plane is travelling towards west at a speed of 1800 km/h.

What is the voltage difference developed between the ends of the

wing having a span of 25 m, if the Earth's magnetic field at the

location has a magnitude of 5 x 10- 4 T and the dip angle is 30° ? 3

(i) ~ ~ ~-~~colG! WI ~ R<1l1 ~ I

(ii) ~ ~ ~ ~ fu:m Chl 3ffi 1800 km/h Chl ~ it ·1f<1~I.-j ~ I ~ ~

~ ~ W 25 m ~ ~ I ~ fuU 1:R ~ ~ ~ ~) <1fc:: ~

~ 1:R 'I~ ~ -q~colG! ~ CfiT ~ 5 x 10- 4. T ~2lT ;rfu itur CfiT l1R

30° ~ ?

~ In Young's double slit experiment, monochromatic light of wavelength630 nm illuminates the pair of slits and produces an interferencepattern in which two consecutive bright fringes are separated by8·1 mm. Another source of· monochromatic light produces theinterference pattern in which the two consecutive bright fringes areseparated by 7·2 mm. Find the wavelength of light from the secondsource.

What is the effect on the interference fringes if the monochromaticsource is replaced by a source of white light? 3

*r ~ ~-WU m if ~. ~ ~ rir ~ m ~~ 630 nm c1~'I~c4 ~

....--.---...!X WW[f CfiT ~ m .1:R OGlf<1COo(.UI ~. ~ ~ ~ ~ ~ ~ ~

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CfiT c1{'I~~ ~ ~ I

<1fu: li,COejUn WW[f ~ rir m >rcI1m ~. ~ it ~ ~ ~ err OGlf<1COo(.UI ~

1:R CF1T >f'liTCf ~ ?

~ Draw a schematic arrangement of the Geiger - Marsden experiment.How did the scattering of a-particles by a thin foil of gold provide animportant way to determine an upper limit on the size of the nucleus?Explain briefly. 311WR-~ m CfiT ~ H~l.{UI ~ I ~ Chl ~ cp;;jt mr a-C11UIT CfiT~ ~ m~ ~~ cp1 ~ ~ ~ m CfiT ~Q\Cll.{UI ~ GAT ?

~~ifcroH~ I

5511 10

L'DistingUiSh between sky wave and space wave propagation. Give abrief description with the help of suitable diagrams indicating howthese waves are propagated. 3~ ~ ~. ~ 3Wfim ~ ~ -if ~ ~ I ~ 3W CfiT \-tQI~("j1 ~,

?;fQ ~ ~ ~ fcfi ~ ~ ~ m~ QTffi ~, ~ ~ femur ~ I

~ With the help of a suitable diagram, explain the formation of depletion. region in a p-n junction@ow does its width change when the junction

is (i) forward biased, and (ii} reverse biased ? 3

~ ~ CfiT \-tQI~("j1 ~ fclitfr p-n m'l:l -if ~ ~ cnr ~ ~ ~ I ~ cnr

(i) 3-i~rcf~ICP ~, ~ (ii) lj~-q~~~lcn ~ Cfi"8 LR ~ ~ CfiT ~ ~ ~

r.~·Will~?

~ive a circuit diagram of a common emitter amplifier using an n-p-ntransistor. Draw the input and output waveforms of the signal. Writethe expression for its voltage gain. 3fctim n-p-n ~ir~~'\cpr ~ ~ ~ -jct-j",fcp ~ cpr ~ .m& ~ I~ ~ ~ (f~ R*r ("j~'I~Y ~ I ~ ~ ~ ~ ~ ~ ~ I

/'U•./Draw a plot showing the variation of binding energy per nucleon

versus the mass number A. Explain with the help of this plot therelease of energy in the processes of nuclear fission and fusion. 3

~ A -if yR.qJ.; ~ ~ ~ ~ "5lfu ~3fR -if ~.f ~ ~ ~ ~

::rrli ~ I ~ '!fT1l1 Ch1 \-tQI~("j1 ~ ~ 'Bw:R ~ ~ ~ CfiT ~3TI

-if~~~~~ I

28. Draw a schematic sketch of a cyclotron. Explain briefly how it worksand how it is used to accelerate the charged particles.

(i) Show that time period of ions in a cyclotron is independent ofboth the speed and radius of circular path.

(ii) What is resonance condition ? How is it used to accelerate thecharged particles ? 5

OR

Two straight long parallel conductors carry currents II and 12 inthe same direction. Deduce the expression for the force per unitlength between them.

Depict the pattern of magnetic field lines around them.

5511 11 p.T.a.

(b) A rectangular current carrying loop EFGH is kept in a uniformmagnetic field as shown in the figure.

ElF

I

H ; G

(i) What is the direction of the magnetic moment of thecurrent loop?

(ii) When is the torque acting on the loop (A) maximum,(B) zero? 5

*i1~cK1l~I'i cor, ~ ~ ~ I ~ C:W:r~UIIc.11~2lT .~. ~ ~ ~ Cfi8it~~~~it~~l

(i) ~ ~ fcfi *i1~q.ctJ~I'i it ~ cor 3i/C;f ctctlIc.1 3WRT ctt ~ ~ ~ 'q"2T

ctt ~ ~ 'R f.rlR -;r@ ~ I

(ii) ~ ctt "ffif cp:rr ~ ? ~ ~ ~ ~Cfi8 it ~ ~ ~ ~1%?:rr ~ ~ ?

3l~

(a) ~ m~~ "B11RR ~ ~ ~ m ,Kw it ~ 11 ~ 12 ~ m WI"~ I ~~>!fu~~'R~'~fu"Q:~~~ I'"

~ -:qffi .am :!~ctlIGl ~ WTaTI ~ ~ ~ ~ I

(b) m it ~ ~ ~3iIGj<1lctll( ~ ~ EFGHOO .. ,.'L~it~-zmm~ I

ElF

I

H ; G

(i) mu ~ ~ :!~ctllGl ~ cn1 Kw cp:rr ~ ?

(ii) ~ 'R ~ ~-~ ~ (A) .a:IT~, (B) ~ ~ ?

55/1 12

(b) A rectangular current carrying loop EFGH is kept in a uniformmagnetic field as shown in the figure.

E'F

I..L..

H i G

(i) What is the direction of the magnetic moment of thecurrent loop ?

(ii) When is the torque acting on the loop (A) maximum,(B) zero? 5

~1~~~lrj CfiT. ~ 31fu9 ~ I ~ cW:\'>lU 1I~1 (f2lT ~ CfiUTf <if ~ em­if~~<if~if~~ I

(i) ~ ~ fCfi ~I~~~I.-f if am CfiT 311~Jq,I~ am q:it ~ (f2lT ~ 119.:f

q:it ~ ~ 'R f.rR ~ C:fi\(fT I

(ii) ~ q:it ~ cp:rr ~ ? ~ CfiUTf <if ~em- if ~ ~ ~ m

fCfi"lJT \i!Tffi ~ ?

3l~

(a) ?J m~~ ~ ~ it ~ m ,~ if ~ II (f2lT 12 ~ m ~

~ I ~~>rfu~~'R~.~~~~~ I

~ -:qffi am: 1~q,1~~ ~3TI ~ ~ <if ~ I

(b) fq;r if ~ ~ ~3-tI~dlq,l\ ~ ~ EFGHM , .'L~ if ~ \i!Tffi ~ I

E'F

I..L..

H i G

(i) ~ ~ ~ 1~q,1~~ q:it ~ cp:rr ~ ?

(ii) ~ 'R ~ ~-~ ~ (A) 31f~, (B) ~ ~ ?

55/1 12

29. (a)

(b)

What are eddy currents? Write their two applications. -

Figure shows a rectangular conducting loop PQSR in which arm

RS of length 'l' is movable. The loop is kept in a uniform

magnetic field 'B' directed downward perpendicular to the plane

of the loop. The arm RS is moved with a uniform speed 'v'.

X R X

X S X

r

I

1

X

X

X

X

p Xr­X

X

X

X

Q X

X

X

X

X

x

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

v

Deduce an expression for

(i) the emf induced across the arm 'RS',

(ii) the external force required to move the arm, and

(iii) the power dissipated as heat.

OR

(a) State Lenz's law. Give one example to illustrate this law. "The

Lenz's law is a consequence of the principle of conservation ofenergy." Justify this statement.

5

(b)Deduce an expression for the mutual inductance of two longcoaxial solenoids but having different radii and different numberof turns. 5

55/1 13 p.T.a.

(b) fq;r it ~ 3-W-ldlcpl"- ~ ~ PQSR ~ 'flIT ~ ~ ~ RS tt ~'l' ~ ~ <:ffi 11fu ~ ~ ~ I <:ffi. ~ fcnm ~CP*il-{I.-j1l-qcpl~ $I" 'B' it mrr

~ ~ ~ it dB it ~l-qqQ. ~. fuJ! ~ I ~. RS <it ~CP*il-{I.-j~ 'v'

it11fu~~~1

X R X

X S X

1

l

1

X

X

X

X

p X

X

X

X

X

Q X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

v

30. (a) (i)

55/1

r~+.•-IfC:1r~d it ~. ~ ~ ~ :(i) ~ 'RS' it rnu 1R ~ fcrWl-~ qc;r,

(ii) :pIT <it 11fu ~ it ~ 3-i Iq~~en <ifiWqc;r, (f2lT

(iii) ~ it ~ it ~ a;r.1 I

3l?:lCIT

(a) ~ COT f.:r:r1:r fufurQ: I ~ cx:rr&IT ern- it ~ ~ 6~IQ,,-ul ~ I "~COT

~ ~ ~ f.:r:r1:r COT ~ -qftuw:r ~ I" ~ qiZR tt ~ ~ I

(b) ~ ~ wwJt \4K-iIf~CPI3TI, ~. ~ (f2lT W tt ~ M?r-M?r t it~*ur.it~~~~ I

Draw a labelled ray diagram to show the formation ofimage in an astronomical telescope for a distant object.

(ii) Write three distinct advantages of a reflecting typetelescope over a refracting type telescope~

(b) A convex lens of focal length 10 cm is placed coaxially 5 em awayfrom a concave lens of focal length 10 em. If an object is placed30 em in front of the convex lens, find the position of the finalimage formed by the combined system.

OR

14

5

(a) With the hcl.p of a suitable ray diagram, derive the mIrrorformula for a concave mirror.

(b) The near point of a hypermetropic person is 50 em from the eye.

What is the power of the lens required to enable the person toread clearly a book held at 25 em from the eye ? 5

(a) (i) 00 ~. ~ in ft;m: .(gl~~l~ ~"'C\~ICO"[ro >lrd~~ ~ ~ in ft;m:

",,:1:. ~ >!Cfim~ 31l& ~ 1

(ii) ~ ww: in~"'C\~lcol cn1 ~ if ~ ww: in ~",C\~rcolin (fA ~BTl1~ I'

(b) 10 em ~ ~ in fcnm ~ ~ it ~ ~"5 em ~ -en:~ 10 em

~~CfiT~~~~1 <1fu: ~ ~c€t~~in~

30 em ~ W, -ill ~ f.rcw;r "[ro ~ 31RPi >lrd~~cn1 ~ ~

~I

(a) ~ >!Cfim ~ 31l& cn1 ~QI~dl it fcnm ~ ~ in ft;m: ~ ~

~~I

(b) ~ ~ it ~ fcnm oqfui in Relic: ~ cn1 ~ it ~ 50 em ~ I ~

~ cn1 m Cf<1T~ ~ ~C?I~dl it CfQ oqfui ~ c€t ~ it 25 em ~

-en:~~trq;~~ ?

55/1 15 97100