Chapter 2 Physics

17fkdñ,fha fnod §u i|yd h'

m%ldY úoHdj yd iïnkaO ixisoaê

⌂

⌂

⌂

Tm ±uQ ;, mDIaGj,ska yd jl% mDIaGj,ska isÿ jk mrdj¾;kh" tAiïnkaO ixisoaê iy tAjd tÈfkÞ lghq;= myiqlr .ekSu i|ydfhdÞf.k we;s wdldrh"

wdf,dla j¾;kh yd iïnkOa ixios êa " udkj lgh;q = i|yd fhdÞ.kka d wdldrh"

ldpj,ska iEfok úúO m%;sìïn iïnkaO ixisoaê yd m%ldY WmlrKks¾udKh lsÍu i|yd tAjd fhdÞf.k we;s wdldrh" ms<sn| j wkafõIKh lsÍug wjYH"

2

fuu mdvu yeoEÍfuka miq j Tng"

ksmqK;d ,nd .ekSug yelsjkq we;'

18 fkdñ,fha fnod §u i|yd h'

2'1 Tm ±uQ ;, mDIaGj,ska iy jl% mDIaGj,ska isÿ jk mrdj¾;khwmg iQ¾hhd" ;re" myka" .sks±,a wdÈh ±lsh yelafla tAjd wdf,dal m%Nj ksid

h' tAjdhska ksmojk wdf,dal Odrdjka wfma weiaj,g .uka lrk fyhsks' fjk;a

fndfyda foaj,a wmg ±lsh yelafla iQ¾hhdf.ka fyda myka jeks by; lS

m%Njhlska msg lrkq ,nk wdf,dalh tA tA øjHh u; m;s; ù tAjdhska wdf,dalh

wmf.a wei fj;g meñfKk ksid h' fufia wdf,dalh hï mDIaGhla u; je§

fjk;a ÈYdjla Tiafia wdmiq .uka lsÍu wdf,dal mrdj¾;kh kñka ye¢kafõ'

wdf,dal m%Njhla fkd jk pkaøhd wmg ±lsh yelafla iQ¾hhdf.ka msg jk

wdf,dal lsrK pJøhdf.a mDIaGh u;ska mrdj¾;kh ù wmf.a wei fj;g

meñfKk ksid h'

wdf,dal mrdj¾;kh

fndfyda mDIaG úúO ÈYd Tiafia wdf,dalh mrdj¾;kh lrhs' o¾mK jeks

b;d iqug mDIaG úêu;a wdldrlg wdf,dalh mrdj¾;kh lrhss' tys m%;sM,hla

jYfhka m%;sìïn o iEfoa'

wdf,dla lrs Khl a o¾mKhl a u; m;;s jk úg th 2'1 rEmfh y s olja d we; s

wdldrhg mrdj¾;kh fõ' o¾mKh fj; tk lrs Kh jk w;r

o¾mKfhk a neyer j hk lrs Kh mrdj¾;k lrs Kh fõ' mrdj¾;kh iÿs jk

,lIa Hfh a igs ;, o¾mK mDIGa hg w¢k q ,nk ,ïnl f¾Ldj wN,s ïnh fõ' m;kh

jk lrs Kh wN,s ïnh iu`. idok fldKa h m;k fldKa h jk w;r mrdj¾;kh

jk lrs Kh wN,s ïnh iu`. idok fldKa h mrdj¾;k fldKa h fõ' fuu kÍs lIa K

mokï lrf.k wdf,dla mrdj¾;k khs u bÈßm; a lr we;' tja d my; oelfa õ'

m;k lsrKh

i = r = mrdj¾;k fldaKh

m;k fldaKh

wN,s ïnh

m;k lsrKh i r

;, o¾mKh

2'1 rEmh - ;, o¾mKhla u`.ska isÿjk mrdj¾;kh

mrdj¾;klrs Kh

mrdj¾;k kshu

1' m;k fldaKh" mrdj¾;k fldaKhg iudk fõ'2' m;k lsrKh" mrdj¾;k lsrKh yd m;k ,laIHfha§ mDIaGhg we`os

wNs,ïnh tl u ;,hl msysgd we;'


;, o¾mKj, iEfok m%;sìïn

;, o¾mKhlska wm olakd m%;sìïnh ;srhla u;g .; fkdyels h' tjeks m%;sìïnhla w;d;aúl m%;sìïnhla f,i ye¢kafõ' ;srhla u;g .; yels m%;sìïnhla ;d;aúl m%;sìïnhla f,i ye¢kafõ' ;, o¾mKhlska m%;sìïnhla ,efnk whqre ±lafjk lsrK rEm igyk my; 2'3 rEmfha ±lafõ'

fuu m%;sìïnfha ,laIK

• w;d;aúl m%;sìïnhls'

• Wvql=re m%;sìïnhls'

• jia;=fõ isg o¾mKhg we;s ÿr" o¾mKfha isg m%;sìïnhg we;s ÿrg iudk h'

• m%;sìïnfha m%udKh jia;=fõ m%udKhg iudk h'

• m%;sìïnh md¾Yaúlj wmj¾;khù mj;S' ^2'3 rEmh&

2'3 rEmh - ;, o¾mKhlska m%;sìïnh

ji;a j= m;% ìs ïnh

;, o¾mKh

BB

ls%hdldrlu 2'2

lrs K fmÜáhla k¾s udKh lr wdf,dal mrdj¾;kh ksÍlaIKh lru'q fï i|yd 12 cmx12 cm x12 cm mu% dKfha ldâ fndâa fmÜáhla idÞ .kak' fmÜáfha A uqyqKf;a lemuq la fhdÞ B uyq Kq f;a o iÿs rla ;kkka ' 2'2 rEmh&

2'2 rEmfha lemqu muKla újD;j ;sfnkakg yer A uQK;g l¿ lvÞis w,jkak' ,S l=Üáh;a ;, o¾mKh;a lemqu bÈßfha r|jkak' iqÿ lvÞishla WmlrK lÜg,hg háka ;nkak' B isÿr ;=<ska l=vd úÿ,s n,anhla we;=,a lrkak' n,anhg úÿ,sh imhd" fhdÞ.;a lemqu yryd wdf,dal lsrK loïnhla ;, oramKhg m;s; ùug i,iajkak' fuu m;k lsrK ;, o¾mK mDIaGhg meñfKk úg thska msg ù hk mrdj¾;k lsrK Tng ±l.; yels h' iqÿ lvÞish u; mekai,lska tu lsrK fofla ud¾. ,l=Kq lrkak' ;, o¾mKfha msysàu o tA u; ,l=Kq lrkak' iqÿ lvÞish bj;a fldg mrdj¾;k ,laIfha wNs,ïnh o¾mKhg ,ïnl j w¢kak' fldaKudkhla Ndú; fldg m;k fldaKh yd mrdj¾;k fldaKh ukskak' Tnf.a ksÍCIK mrdj¾;k kshu iu. ii|kak

fuu ls%hdldrlu w÷re ia:dkhl § l< hq;=h'

2'2 rEmh - wdf,dal mrdj¾;kh ksÍlaIKh

,S l=Üáh

;, o¾mKh

úÿ,smyk

fmÜáhlemuq

iqÿ lvÞishA

B

ls%hdldrlu 2'1

;, o¾mKhla hïlsis fldaKhlska ysre t<shg w,a,d thska wdf,dalloïnhla ì;a;shla u;g ,nd.kak' ;, o¾mKh fj; yd o¾mKfhkabj;g wdf,dal loïn .uka lrk wdldrh ksÍlaIKh lrkak'

,efnk whqre

fkdñ,fha fnod §u i|yd h'

Tn f,day yekaolska Tnf.a uqyqfKa m%;sìïnh ±l ;sfí o@ yekafoa bÈßmiska yd msgqmiska tlsfklg fjkia iajNdjfha m%;sìïn Tng ±lsh yels h' fufia isÿ jkafka yekafoa mDIaG jl% o¾mK f,i ls%hd l< ksid h 2'4 rEmh&'

md¾Yaúl wmj¾;kh'

;, o¾mKhla ;=<ska lsishï jia;=jl m%;sìïnhla fmfkk úg wÞ< jia;=fõol=Kq mi m%;sìïnfha jï me;a;g;a" jia;=fõ jï mi m%;sìïnfha ol=Kq mig;a Èiajk wdldrhg yria w;g me;s udre ù fmfka' fuu ixisoaêh md¾Yaúl wmj¾;kh kñka ye¢kafõ' fuh 2'3 rEmfhka meyeÈ,s lr we;' ,dïmqfõ jï mig iúlr we;s wlaIrh m%;sìïnfha Èia jkafka ,dïmqfõ ol=Kq miska f,i h' fuu ixisoaêh .s,ka r:hl bÈßmi f,i i`oyka lsÍug o Wmfhda.S lrf.k we;' jdykj, iúlr we;s me;s lKakdäj,ska miqmiska tk jdyk ksÍlaIKh lsÍfï§ md¾Yaúl wmj¾;kh ksid ßheÿrkg

by; jpkh AMBULANCE f,i ksjerÈj oel.; yels h' ta wkqj .s,kar:hla myiqfjka y`ÿkd.ekSug Tjqkg yelsfõ'

f.da,fha flaJøh o¾mKfha jl%;d

flakaøfhys C f,i ,l=Kq flf¾' O%ejh"

m%Odk wlaIh iy jl%;d wrh (PC) 2'5 rEmh iy 2'6 rEmh& olajd we;'

jl% o¾mK •

20

wj;, P P

2' mrdj,hsl o¾mK

wj;, mDIGa h

2'4 rEmh - f,day yekaol jl% mDIaGW;;a , mDIGa h

W;a;, o¾mK

1' f.da,Sh o¾mKwj;, o¾mK

wj;, o¾mKhl mrdj¾;k jl% mDIaGh we;=<g tî mj;sk w;r W;a;, o¾mKhl mrdj¾;k jl% mDIaGh msg;g fkrd ;sfí' l=vd jl% o¾mK idudkHfhka idÞ.kq ,nkafka f.da,dldr mrdj¾;k mDIaGj,sks'

2'5 rEmh - f.da,Sh o¾mK wj;, o¾mKhW;a;, o¾mKh

Oe% jh

P

jl%;d flakaøh

POe% jh

mO% dk wlIa h

C C• •

C W;a;,


ls%hdldrlu 2'3

;rula >klï mdroDYH ;=kS ùÿre ;yvqjla" wj;, o¾mKhla" W;a;, o¾mKhla yd l=vd fïihla imhd .kak' ^fuu ls%hdldrlu l< hq;af;a iQ¾hdf,dalh iys; újD; ia:dkhl § h'& m<uqj wj;, o¾mKh" tys mrdj¾;k mDIaGh by<g isák fia fïih u; ;nkak' wj;, o¾mKhg yß fl<ska ùÿre ;yvqjla w,a,d tA u; b;d §ma;su;a wdf,daluh ;s;la ,efnk f;la iSre udre lrkak' fuhska o¾mKfha m%Odk kdNsh yd kdNSh ÿr y÷kd.kak' bkamiq j W;a;, o¾mKh fïih u; ;nd ùÿre ;yvqj fmr fuka Wäka w,a,d ksÍlaIKh lrkak' tys § §ma;su;a wdf,daluh ;s; fjkqjg ;rula úYd," §ma;sfhka wvq jD;a;hla Tng fmfka' fuys § wj;, o¾mKh iuÕ b;d §ma;su;a wdf,dal ;s;la ,efnkqfha tys kdNSh ÿßka nj;a W;a;, o¾mKhl tjeks ;s;la fjkqjg ;rula úYd," §ma;sfhka wvq jD;a;hla Èiajk nj;a Tng ksÍlaIKh l< yels h' 2'8 rEmh&

f.d,a hS o¾mKfh a Oe% jh P yd jl;% d flka øa h C yryd w¢k q ,nk ir, f¾Ldj mO% dk wlIa h f,i kï flf¾' Oe% jh hk q f.d,a hS o¾mKfh a mDIGfh a uOH ,CIh hs'

f.da,Sh o¾mKh ;+<ska isÿ jk mrdj¾;kh

wj;, o¾mKhl m%Odk wlaIhg ióm j yd iudka;r j .uka lrk

wdf,dal lsrK" o¾mKfha mrdj¾;kfhka miq wNsidÍ j m%Odk wlaIh u; we;s F kï jQ tla ,laIHhla yryd .uka lrhs' W;a;, o¾mKhl m%Odk wlaIhg iómj yd iudka;r j .uka lrk wdf,dal lsrK o¾mKfha mrdj¾;kfhka miq

wmidÍj msg;g úyso hkafka F kï jQ tla ,laIHhl isg meñfKk mßoafoks'

fuu wjia:d foflys § u F ,laIHh tla tla jl% o¾mKfha m%Odk kdNsh f,i

ye¢kafõ' P isg F olajd ÿr kdNSh ÿr f,i ye¢kafõ' fuu wjia:d foflys § u O%ejh yd jl%;d flakaøh w;r yß ueÈka kdNsh msysghs 2'7 rEmh&'

wj;, o¾mK j,ska iEfok m%;sìïn

W;a;, o¾mKh ^wmidÍ o¾mKh &

2'7 rEmh - jl% o¾mKj,skawNsirKh yd wmirKh isÿjk whrq e

2'8 rEmh

ùÿre ;yvqj

wj;, o¾mKh W;a;, o¾mKh

.C .F P.. P F C.

wj;, o¾mK^wNsidÍ o¾mK&


2'9 rEmh

1 2 3

wj;, o¾mKj,ska iEfok m%;sìïn

wj;, o¾mKhla bÈßfha ;nd we;s jia;=jl" m%;sìïnh msysgk ia:dkh ksjerÈ j fidhd .ekSu i|yd my; olajd we;s lsrK mrdj¾;kh jk wdldr y;frka wju jYfhka folla fyda fhdÞ.; yels h'

1' C ^jl%;d flakaøh& yryd .uka lrk lsrKh mrdj¾;kfhka miq kej; C yryd u .uka lrhs 2'9 a rEmh&'

2' m%Odk wlaIhg iudka;r j .uka lrk wdf,dal lsrKh mrdj¾;kh ù F yryd .uka lrhs' 2'9 b rEmh&'

3' F yryd .uka lrk lsrKh mrdj¾;kfhka miq m%Odk wlaIhg iudka;r j .uka lrhs 2'9 c rEmh&'

4' P fj;g .uk a lrk lrs Kh mrdj¾;kfhk a mi q j ;, o¾mKhl fuk a m;k fldKa hg iudk mrdj¾;k fldKa hl a idoñk a .uk a lrh s 2'9 d rEmh&'

my; ±lfa jk rEm igyk a uÕks a by; lrs K j¾. y;r meyeÈ, s flf¾'

jia;=j F yd P w;r m%;sìïnhw;d;aúl " Wvql=re " úYd, "o¾mKh msgqmi

ji;a j= F yd C w;r m;% ìs ïnh;d;aúl" hál=re" úYd," C g

wE;ks a

by; ±la jQ lsrK mrdj¾;kh jk wldr Wmfhda.S lr .ksñka lsishï jia;=jla wj;, o¾mKhl úúO ia:dkj, msysá úg ,efnk m%;sìïnj, msysàu" m%udKh yd iajNdjh my; ±lafjk lsrK rEm igykaj,ska ksrEmKh flf¾ ^2'10 rEmh&'

P F C

P 0 F I C

.

.

(b)

(d)

P F C

. .

(c)

P F C

.

jia;=j F u; m%;sìïnhwkk;a fha

P C

F

C F P

(a)

F o C

IP

ji;a j= wkk;a fh"a m;% ìs ïnh"

hál=re l=vd F u;jia; =j C g wE; sk a "

m;% ìs ïnh ;d;úa l" hálr= e

l=vd C yd F w;r

jia;=j C u;" m%;sìïnh

;d;aúl" hál=re jia;=fõmu% dKhg iudk

2'10 rEmh - wj;, o¾mKj,ska iEfok m%;sìïn

by; i|yka úfYaI lsrK folla Wmfhda.S lrf.k iqoqiq mßudKhlg 2'11

rEmfha mßÈ lsrK igykla w¢kak' fuys § ,efnk m%;sìïnh O%ejfha isg 12 cm

ÿßka msysgd we;' jia;=jg jvd úYd, h' m%;sìïn Wi 4 cm fõ' th hál=re jk

w;r ;srhla u;g ,nd .; yels neúka ;d;aúl m%;sìïnhls'

úiª ksoiqk #-

kdNSh ÿr 4 cm jQ wj;, o¾mKhla bÈßfha 6 cm ÿßka 2 cm Wi jia;=jla

;nd we;' thska ,efnk m%;sìïnfha msysàï m%udKh yd iajNdjh fidhkak'


P

O

O

F C CP

F

I P O F

C

mejreu 1

wj;, o¾mKj,ska iEfok m%;sìïn fiùu'

my; i|yka o;a; wkqj lsrK rEm ks¾udKh lr" iEu wjia:djl § u ,efnk m%;sìïnj, msysàu m%udK iy iajNdjhka úia;r lrkak'

ish¨ u lsrK rEm i|yd wj;, o¾mKfha kdNSh ÿr 2 cm f,i;a jia;=fõWi 2cm f,i;a i,lkak'

1' jia;= ÿr 5 cm 2f j,g jeä& 2' jia;= ÿr 4 cm 2f u;& 3' jia;= ÿr 3 cm(f yd 2f w;r& 4' jia;= ÿr 2 cm (f u;)5' jia;= ÿr 1 cm (f wvq P iy F w;r) m%;sìïn ÿr yd m%;sìïn Wi uek" igyka lr tlsfkl ikaikaokh lrkak'

2'11 rEmh - wj;, o¾mKhllska iEfok m%;sìïnhl msysàu yd m%udKh

m%;sìïn ÿr = 12 cm

jia;= ÿr = 6 cm

jia;= Wi 2 cm4 cm

kdNsh ÿr

m%;sìïn Wi 4 cm

P F A

B

I


W;a;, o¾mKj,ska iEfok m%;sìïn

W;a;, o¾mKhlska iEfok m%;sìïnh ksje/È j fidhd .ekSu i|yd my; i|yka úfYaIs; lsrK fol Wmfhda.S lr.; yels h rEmh 2'12 n,kak&'

1' m%Odk wlaIhg iudka;r j .uka lrk wdf,dal lsrK m%Odk kdNsfhaisg tkakdla fia mrdj¾;kh ù wmidÍ j .uka lrhs'

2' C ^jl%;d flakaøh& fj; fhduq ù .uka .kakd TskEu lsrKhla" mrdj¾;kfhka miqj kej; C yryd u .uka lrhs'

mrdj,hsl o¾mK

mrdj,hsl mDIaGhla iys; j ilia lr.kq ,nk jl% o¾mKhlg mrdj,hsl o¾mKhla hehs lshkq ,efí' m%Odk wlaIhg iudka;r j mq¿,a wdf,dal loïnhla tl u ,laIHhlg kdNs.; ùu mrdj,hsl o¾mKhl isÿ fõ'

m%Odk wlaIhg iudka;rj m;s;jk lsrK i|yd iaÓr kdNshla wj;, mrdj,hsl o¾mKhlg we;' tneúka mrdj,hsl o¾mKhlska isÿjk mrdj¾;kh jvd ld¾hlaIu yd t,ÞhS tlls 2.13 rEmh&.

m%;sìïnh (Wvql=rehs " w;d;aúlhs" l=vd hs'

2'12 rEmh - W;a;, o¾mKhlska m%;sìïn iEfok whqre

m;% ìs ïnh

jia;=j

tAl ,laIh kdNsh &F

2'13 rEmh - mrdj,hsl o¾mKhl mrdj¾;k ls%hdj,sh

f.da,Sh wj;, o¾mKhlska isÿ jk mrdj¾;kh jvd ld¾hlaIu yd M,ÞhS fkdjkafka, tys m%Odk wlaIhg iudka;rj yd wE;ska tk lsrK tlu ,laIHhl § kdNs.; fkdùu ksid h.

O PI F C

.

F


wj;, o¾mKj, Ndú;

01' ,dïmq mrdj¾;lh

jdyk ,dïmq yd úÿ,s mkaoïj, mrdj¾;lhka wj;, mrdj,hsl o¾mK fõ' n,anfha iQ;s%ldj o¾mKfha iaÓr kdNsh u; ;eîfuka iudka;r wdf,dal loïnhla mrdj¾;kh l< yels h 2'18 rEmh&'

;, o¾mK yd jl% o¾mKj, Ndú;

;, o¾mKj, Ndú;

! lkakdä fïi

! Ñ;%má.; lsÍïj, § úúO jia;+ka wdf,dalj;a lsÍug

! nyqrEfmalaIh (kaleidoscope) iE§fï §" 2'14 rEmh&

! wKaùlaIj, lÞj u; wdf,dalm%fCIamKh lsÍug 2'15 rEmh&

! mÍlaIh (periscope) ks¾udKh lsÍfï § 2'16 rEmh&

2'14 rEmh - nyqrEfmalaIh

;, o¾mK

;, o¾mKh

lÞj

wdf,dal lsrK

m%ldY k<h

jia;=j

2'16 rEmh - mÍlaIhl wdf,dal lsrK.uka lrk whrq e

2'18 rEmh - ,dïmq mrdj¾;lh

l%shdldrlu 2'4

mÍlaIhl wdlD;shla iE§u

jD;a;dldr ;, o¾mK folla yd ma,diaála fnda;,hla ^fu.d îu fnda;,hla& fhdÞ .ekSfuka fujeksm%laafIamhla idÞ .; yels h' fuh Ndú; fldg ;dmamhlg msgqmiska we;s fohla my< isg ne,sh yelsh' 2'17 rEmh&

450

o¾mK

2'15 rEmh - wkaùlaIhl lÞj u;wdf,dalh m%lafIamKh lrk whqre

iÿs re 45 wdk;j

;nd we;s ;,

2'17 rEmh - mÍlaIhl wdlD;sh

o

o¾mK


2'19 rEmh - wj;, o¾mKhNdú;fhka wKaùlaIhlgwdf,dalh ,nd .ekSu

wj;, o¾mK

zfrd.a kS fa .a o;a mßs lia uS i|yd o

zwe;eï ÿf¾laIj, iudka;r wdf,dal loïn wNsirKh lr .ekSug o

z/jq, lemSfï lkakdä f,i o fhdÞ.efka'

wj;, o¾mKfha kdNSh ÿrg jvd flá ÿrlska uqyqK msysá úg" uqyqfKa úYd,s; m%;sìïnhla o¾mKfha Èia fõ' iqug /jq, lemSulg fuhska myiqjla ,efí'

W;a;, o¾mKj, Ndú;

1' jdyk me;s lkakdä j,g fndfyda úg W;a;, o¾mK Ndú; flf¾' ;, o¾mK j,g jvd úYd, mrdihl m%;sìïn W;a;, o¾mK j,ska ,nd.; yels h' tfuka u rd;%S ld,fha § msgqmi jdykj,ska ksl=;a jk wdf,dal loïnh wmidß ù hEu ksid;a ßheÿrkaf.a wei fj; wdf,dal loïn b,lal fkdjk ksid;a fïjd Ndú;h iqÿiqh 2'20 rEmh&'

2' jdykj, hg me;a; ksÍlaIKh lsÍu i|yd wdrlaIl ks<OdÍka úYd, W;a;, o¾mK fhdÞ .kq ,efí'

2'2 wdf,dal j¾;kh yd iïnkaO ixisoaêwdf,dal j¾;kh hkq wdf,dal lsrKhla tla mdroDYH udOHhl isg fjk;a mdroDYH udOHhlg we;=¿ ùfï § ÈYdj fjkia ù .uka lsÍuhs' ^wdf,dal lsrKfha isÿjk keóuhs&' udOH folla ie,l+úg wdf,dalh jvd fõ.fhka .ukalrk udOHh úr, udOHh f,io wfkl m<uq udOHhg idfmalaIj .yK;r udOHh f,io ye¢kafõ' ùÿre" c,h" m,a diáa l a jek s øjH jd;hg jvd .yK;r udOH fõ' tl;a rd mdroDYH udOHhlks a lrs Khl a .uk a lÍs fï § fjki a mdroDYH udOHhl a uKq .eiKq q úg tu lsrKfha my; i|yka yeisÍu ±lsh yel s h' úr, udOHhl igs .yK;r udOHhlg wdf,dla lrs Khl a mús fik úg tu lrs Kh wN,s ïnh foig uol a keó .uk a lrh's

m%ldY k,h

wdf,dla h'

o¾mKh'

lÞj

wj;,

02' ixhqla; wKaùlaIhl

m%lafIam o¾mKh

wKùa lIa lÞfõ we;s kos ¾Ylh fyd¢ka wdf,dla u;a lÍs u i|yd fuy§s wj;, o¾mKh fhdÞ .efk'a

;, o¾mKh

2'20 rEmh - ;, yd W;a;, o¾mKj, wdf,dal mrdihka ,nd.ekSuo¾Yk m:h mgqh

W;a;, o¾mKh

o¾Yk m:h mq`M,ah


2'21 - rEmh' wdf,dal j¾;k lsrK rEm igyk

m;k lsrKhwN,s ïnh

j¾;klrs Kh'

ùÿre

jd;h

wN,s ïnh

j¾;k kshu

1. m;k lsrKh" j¾;k lsrKh yd m;k ,laIHfha § udOHh fjka lrk mDIaGhg we¢ wNs,ïnh tl u ;,hl msysgd we;'

2. wdf,dla h tl;a rd mdroDYH udOHhl igs fjk; a mdroDYH udOHhlg .uk alÍs fï§ iEfok m;k fldKa fh a ihks h; a j¾;k fldKa fh a ihks h; a w;r wkmq d;h khs ;hl's fuu khs uh ifa k,fa . a khs uh (Snell's low) f,i ye¢kfa õ' fufi a ,efnk khs ;h m<u q udOHhg idfmalaIj fojek s udOHfh a j¾;k wxlh fõ' th i|yk alrkfa k a n f,i h'1 2

jd;fh a (air) igs ùÿrej,g (glass) wdf,dla h .uk a lrkfa k a kï j¾;k wxlh ,hs k q ,nkfa k a n f,i h' fuu j¾;k wxlh lis hs ï udOHhlg idfmla Ia j ukks qa g

,nk fyhks a idfmla Ia j¾;k wxlh f,i ye¢kfa õ' m<u q udOHh fjkjq g ßl;a hl afhdÞ.; fyd; a ,efnk j¾;k wxlh fojek s udOHfh a krs fmla Ia j¾;k wxlh fõ'

tla;rd udOHhla ;=< wdf,dalfha fõ.h ksh; jqj;a fjk;a udOHhlg we;=¿ùfï § tys fõ.h fjkia fõ' fuu fõ.h fjkia ùu ksid wdf,dal lsrKh j¾;khg Ndckh fõ'

fuys § wdf,dalh tla udOHhl isg ;j;a udOHhlg msúfik úg j¾;kh isÿjkafka tA tA udOHh ;=< wdf,dalfha fõ.h fjkia jk neúks' udOH folla ie,l+úg úr, udOHhg idfmalaIj .yK;r udOHh ;=< wdf,dalfha fõ.h wvqh.

tfuk a u wdf,dla lrs Khl a .yK;r udOHhl igs úr, udOHhlg mús ifS ï § tu lrs Kh wN,s ïnfhk a bj;g keó .ukalrhs 2'21 rEmh&'wdf,dalh j¾;kh jkafka wehs@

lsrK fmÜáh

iqÿ lvÞish

ùÿre l=Üáh

2'22 - rEmh

ls%hdldrlu 2'5

lsrK fmÜáhla Ndú;fhka j¾;kh ksßlaIKh lruq'

2'22 rEmfha mßÈ iqÿ lvÞishla u; WmlrK ilia lr.kak' lsrK fmÜáhla fhdÞf.k ùÿre lÜ= áfh a tl a mDIGa hl a u; lrs K m;;s ùug i,ija d m;k lrs Kh" k¾s .; lrs Kh" ùÿre lÜ= áfh a mys às u iÿq lvÞifs h a igyk a lr.kka ' iÿq lvÞihs bj;g f.k m;k lrs K iy k¾s .; lrs K we| ùÿre ;<= j¾;k lrs Kh k¾s udKh lrkka '

m;k fldaKh (i)

j¾;k fldaKh (r)

ks¾.; lrKh

fuys § tla udOHhl isg ;j;a udOHhlg wdf,dalh j¾;kh ùu isÿjkqfha j¾;k kshuj,g wkql+,j h'

n = sin i /sin r i = m;k fldaKh r = j¾;k fldaKh1 2


úiª ksoiqk 1

jd;fha isg ùÿre ;=<g wdf,dalh j¾;kh ùfï § ksÍlaIKh lrk ,o m;k yd j¾;k fldaKj, wkqrEm w.hhka my; olajd we;' tu w.hhka Wmfhda.S lrf.k jd;hg idfmalaI j ùÿrej, j¾;k wxlh fidhkak'

úúO øjHj, j¾;k wxl w.hhka lsysmhla fuu j.=fõ ±lafõ' fuu j.=j wkqjÈhuka;s ;=< § wdf,dalfha fõ.h wvq u jk nj;a Bg idfmalaI j c,fha § wdf,dalhgby< fõ.hla we;s nj;a Tng fmkS hkq we;'

udOHh j¾;k wxlhÈhuk;a s 2'42l%jqka ùÿre 1'52m¾iafmlaia 1'49c,h 1'33

2'23 rEmh - jd;fha isg ùÿre j,g

tla udOHhl isg ;j;a udOHhlg wdf,dalh .uka lsÍfï § wdf,dalh j¾;khgNdckh jk nj;a tys § fõ. fjkia jk nj;a Tn okS' tu ksid wdf,dalfha fõ.h weiqßka o tys j¾;k wxlh fufia ±laúh yels h' jd;hg idfmalaIj

udOHhl j¾;k wxlh

úi÷ -1ksoiqk 3 (ß- la;hla ;=< § fyda jd;fha § fyda wdf,dalfha fõ.h 300"000 km s

-1jk w;r ùÿre ;=< § wdf,dalfha fõ.h 200"000 km s fõ'

fï wkqj"

jd;h

ùÿre

ùÿrej, j¾;k wxlh = = 1'5 fõ'300"00 -1

km s200"000 km s-1

j¾;k wxlh }ßla;hla ^fyda jd;h ;=<& wdf,dalfha fõ.h

udOHh ;=< wdf,dalfha fõ.h

wdf,dalh j¾;kh ùu

j¾;k wxlh na g

&

ihska r} 0'532j¾;k fldaKh r}320

ihska150 0'26 ihska450 0'71 ihska600 0'87ihska100 0'17 ihska280 0'47 ihska350 0'57

1'5 1'5 1'5

=

===

1'33 } iólrKh Wmfhda.S lr .kak'

1'33 } fï wkqj ihska r } ihska 45 1'33

0 fõ'

ihska iihska rihska450

ihska r

úiª ksoiqk 2

jd;fha igs wdf,dla lrs Khla c,h u; 45 lks a m;kh fõ' c,fha j¾;k wxlh 1'33 kï" c,h ;<= we;s jk j¾;k fldKa fha w.h fidhkka '

Sin iSin r

= =

na g

& ^ =

na g

& ^

0


j¾;kfha § wdf,dalh keó .uka lsÍu ksid .eUqr ms<sn| jerÈ yeÕSula ,nd fokq we;' rEmh 2'26&' msyskqï ;gdlhl m;af,a ,laIHhlska msg;g tk wdf,dal lsrK c,fhka msg;g hk úg j¾;kh fõ' tA wkqj tu lsrK msysá ia:dkhg u|la by< ia:dkhl isg tu lsrK ksl=;a jkakd fia fmfka' tu ksid ksÍlaIlhl=g fmfkkafka msyskqï ;gdlfha m;a, th msysá ia:dkhg jvd ti ù we;s mßoafoks'

tA wkqj fuys § c,fha i;H .eUqrg jvd wvq .eUqrla j¾;kh ksid fmkakqï flf¾' fuu rEm igyfka i;H .eUqr yd oDYH .eUqr ,l=Kq lr we;' c, mDIaGfh a igs m;,= f,i fmfkk i:a dkhg we; s ÿr oDYH .eUrq f,i;"a c, mDIGa fha isg tys m;=f,a i;H msysàug we;s ÿr" i;H .eUqr f,i;a ye¢kafõ' fïjd c,fha j¾;k wxlhg iïnkaO ù mj;akd iólrKhla fufia ,súh yels h'

úi÷ ksoiqk (- by< isg n,k úg ùÿre l=Üáhlg 6 cm >klula we;s nj fmfka'ùÿrej, j¾;k wxlh 1'5la kï" tu ùÿre l=Üáfha i;H >klu fldmuK o@

1'5 }

i;H .eUqr }}

i;H .eUqr 6

oDYH .eUqr j¾;k wxlh6 1'5 } 9 cm

j¾;k wxlh }i;H .eUqroDYH .eUqr

oDYH .eUrq i;H .eUqr'c,h'

jd;h'

2'26 rEmh - j¾;k M,

2'25 rEmh - c,fha isÿ jk j¾;kh ksid mekai,la u|la keó fmfkk whqre

ls%hdldrlu 2'6 (a) ùÿre Ndckhla c,fhka mqrjd tu c, Ndckh ;=<g ldishla oukak' rEmfha fmfkk mßÈ c, mDIaGh Wäka ldish ksÍlaIKh lrkak 2'24 rEmh&'

2'24 rEmh-wdf,dalfha j¾;kh ksid ldish ti ù fmfkk whqre

(b) 2'25 rEmfha fmfkk wkaoug c, îlrhla ;=<mekai,la ;nkak' c, mDIaGhg Wäka mekai, foi n,kak' mekai, c,h ;=< .s,S we;s wdldrh yd mekai,a ;=v c,fhka ;rula ti ù we;s wdldrhla fmfka 2'25 rEmh&'

i;H .eUqr yd oDYH .eUqr

j¾;kfha § wdf,dalh keó .uka lsÍu ksid hï udOHhla ;=<ska n,k úg tys i;H .eUqr ksis f,i oDYHudk fkdfõ'

2'24 rEmh


2'27 rEmh - ùÿrej, isg jd;hg wdf,dalh j¾;kh ùfï § iEfok fldaK

wjê fldaKh iy mQ¾K wNHka;r mrdj¾;kh

.yK;r udOHhl isg úr, udOHhlg wdf,dal lsrKhla j¾;kh ùfï §

j¾;k lsrKh wNs,ïnfhka bj;g keUqre fõ' 2'27 a rEmh& .yK;r udOHfha m;k fldaKh l%ufhka jeä lrk úg tla;rd wjia:djl § j¾;k lsrKh udOH

fol fjka lrk mDIaGh Tiafia .uka lrhs' ^2'27 b rEmh& tu wjia:dfõ .yK;r udOHfha m;k fldaKh" wjê fldaKh f,i ye¢kafõ' .yK;r

udOHfha m;k fldaKh wjê fldaKh © blau jk ish¨ u lsrK udOH ;=<gu

mrdj¾;kh fõ' fuh mQ¾K wNHka;r mrdj¾;kh hs' 2'27- c rEmh&

ñßÕ=j- mQ¾K wNHka;r mrdj¾;kfha w;a±lSula

wêl ysre rYañh we;s WKqiqï Èkhl iuyrúg Tn ;dr mdrl wE; ksÍlaIKh l<fyd;a tys c,dYhla ;sfnkakd fia Èiajkq we;' fuh ñßÕ=j f,i ye¢kafõ' ñßÕ=jla iEfokafka 2'28 rEmfhka ±lafjk mßÈ jd; ia:r ;=<ska j¾;kh yd mq¾K wNHka;r mrdj¾;kh isÿ ùu ksid h' iq¾hhd u`.ska mdr fyda ldka;drh fyda wdf,dalj;a lrk w;r u tu mDIAGh ;Èkaa WKqiqï lrhs' tu mDIaGj,g wdikak jd; ;Ügq ;Èka r;a ùu ksid m%idrKh ù >k;ajh wvq fõ' túg idfmalaI jYfhka by< we;s jd; ia;rj, jeä >k;ajhla mj;S' wdf,dal lsrKhla by< isg my<g l%u-l%ufhka ;sri fj; j¾;kh ù wjidkfha § tu lsrK ;dr mdr wdikakfha we;s WKqiqï ia;rhg <Õd jkafka wjê fldaKhg jvd jeä fldaKhlsks' túg mQ¾K wNHka;r mrdj¾;kh la isÿ fõ' 2'28 rEmh&

2'28 rEmfha ±lafjk mßÈ wE; we;s jia;=jl isg .uka lrk wdf,dalh ksÍlaIlhdf.a weig ud¾. follska <Õd úh yels h' tys m%;sM,hla jYfhka jia;=jl tys i;H ia:dkfhys isg tk wdf,dal Bg my<ska we;s jia;=fõ hál=re" w;d;aúl m%;sìïnfha isg tkakd fia weig <Õdjkq we;' jia;=j yd ksÍlaIlhd w;r ìfuys fkdmeyeÈ,s m%foaYhla we;' tys mDIaGh È,sfik iq¨ yd j¾;k;djla

(refractivity) mj;S' fï ksid WKqiqï úh<s mdr f;;a mdrla f,i wE;g Èia fõ'

2'3 wdf,dal j¾;kfha ixisoaê udkj lghq;= i|ydfhdÞ .ekSu

jd;h jd;hjd;h

ùÿre ùÿreùÿre

wN,s ïnhwN,s ïnh wN,s ïnh

m;k lsrKh

j¾;klrs Kh

j¾;k lsrKhmDIGA h yryd.uka lrhs j¾;k

lsrKhla ke;

a rEmh b rEmh c rEmh

i1< r

r

i1

i = c2

i2

i3 i3

i > c3


mq¾K wNHka;r mrdj¾;kfha fhÿï - m%ldY fl`È (optical fibers)

m%ldY fl¢ (optical fibers) idÞ we;af;a b;d ;=kS iqkuH ùÿre fyda mdroDYHma,diaála fl¢j,sks' tla fl<jrlska we;=¿ jk wdf,dalh fuys § È.g u mQ¾K wNHka;r mrdj¾;khg Ndckh ù wksla fl<jßka bj;g hhs ^2'29 rEmh&' fl¢ u`.ska wdf,dalh u| jYfhka Wrd .;a; o" fl¢ lsf,daóg¾ .Kkdjla È. jqjo tA ;=< g wdf,dalh we;=¿ jQ mßÈ u §ma;sfhka hqla;j wfkla fl<jfrka msg;g meñfKa' m%ldY fl`È fmdÈhlg wdf,dal k,h (light pipe) hk ku fhfoa' ffjoHjre YÍr wNHka;r fldgia mÍlaId lsÍug;a" úÿ,s ix.%dyljre" ÿrl:k m‚ jqv heùug;a fïjd fhdÞ .ks;s'

m%siau ;=<ska isÿjk mQ¾K wNHka;r mrdj¾;kh

mQ¾K wNHka;r mrdj¾;kh ,nd.ekSug" tla fldaKhla 90° la jQ o wfkl=;a fldaK 45° ne.ska jQ o ms%iauhla o fhdÞ.; yels h' fïjd m%dfhda.sl jYfhka leurdj," ÿf¾CIj, yd fofk;sj, Ndú;d flf¾' ùÿrej, wjê fldaKh wdikak jYfhka 43° ls' tA ksid ùÿre ;=< m;k fldaKh 43° g jeä kï mQ¾K wNHka;r mrdj¾;kh isÿ fõ'

wdf,dal lsrKhla 90° lska yerùu

2'30 rEmfha ±lafjk mßÈ wNs,ïnh Tiafia .uka lrk wdf,dal lsrKhla fkdie,S m%siauh ;=<g we;=¿ ù tys B<`. uQK;g 45°m;k fldaKhla iys; j m;s; fõ' fuh wjêfldaKhg jvd jeä ksid mQ¾K wNHka;rmrdj¾;kh isÿ ù wdf,dal lsrKh m%siaufhawfkla uQK;g ,ïnl j .uka lrhs' wNs,ïnhTiafia tk ksid fuu lsrKh fkdkeó È.g uks¾.; fõ' fuu`.ska wdf,dal lsrKhla 90°

lska yrjd.; yels h' 2'30 rEmh - wdf,dal lsrKhla900lska yerùu

m%ldY flkao

2'29 rEmh - m%ldY flkaolwdf,dalh .uka lrk whqre

450

450

450450

hálr= e w;d;úa lm;% ìs ïnh 2'28 rEmh - ñßÕ=jla weig Èiajk whqre

r;aùu ksid >k;ajh wvqjQ jdhqia:r

>k;ajhjeä jdhq ia:r


2'31 rEmh - wdf,dal lsrKhla 180°lska yerùu

2'32 rEmh - mi%s ua hl wdOdrfhka j¾Kdj,hs ,nd.ekuS '

wdf,dal lsrKhla 180° lska yerùu

2'31 rEmfha ±lafjk mßÈ wdf,dal lsrKh m%siaufhauQK;a foll mQ¾K wNHka;r mrdj¾;khg Ndckhù m%siaufhka msg;g úys§ hkafka m;k lsrKhg iudka;r j yd m%;súreoaO j h' fuys § wdf,dal lsrKh 180° fldaKhlska yer fõ' fuys § wdf,dal lsrK" iDcq fldaKhg iïuqL uQK;g ,ïnl j m;s; l< hq;= h'

m%siauhla yryd isÿ jk wdf,dal j¾;kh

m%siauh ùÿre fyda mdroDYH ma,diaálaj,ska ksujd we;' m%siaufha mdo tlsfklgiudka;r fkd fõ' fï ksid m%siauhlska wdf,dal j¾;kh fõ kï wdf,dal lsrK msg;g tkafka fjk;a ÈYdjla Tiafia h' th wm.ukh fõ' mgq" iqÿ wdf,dal loïnhla m%siaufha uQK;g wdk; j m%siauh yryd .uka l< úg th úúO j¾K .Kkdjlg fn§ hhs' 2'32 rEmh & fuu l%shdj,sh wmlsrKh kñka ye¢kafõ' th isÿjkafka iqÿ wdf,dalh ix>gl j¾K y;lska iE§ we;s neúks' th j¾Kdj,sh f,i y÷kajhs'

m%siauhlska j¾Kdj,shla ,efnk úg ;j;a m%siauhla 2'33 rEmfhys fmfkk wdldrhg ;eîfuka tu j¾K ixfhdackh lr kej; iqÿ wdf,dalh ,nd.; yels h' ksõgka ;eáh Ndú;fhka j¾K ixfhdackh l< yels h'

m%siauh iEu j¾Khla u fjkia m%udKj,ska j¾;kh lrhs'

wvqfjka u wm.ukh jkafka r;= j¾Kh hs' jeäfhka u wm.ukh jkafka oï j¾Kh hs'

fuhska ,efnk j¾K my; i|yka wkqms<sfj<g mj;S' r;=" (R) ;eô,s (O)"

ly(Y)" fld< (G)" ks,a (B)" bkaäf.da (I)" oï (V) jYfhks'

450

450

2'33 rEmh - iqÿ wdf,dalfhka j¾Kdj,sh yd j¾Kdj,sfhka kej; iqÿ

wdf,dalh ,nd.ekSu

m%;sixfhdackh

iqÿ wdf,dalh

wmlsrKh jQj¾Kdj,sh

iqÿ mdg ;srh

iqÿ wdf,dalhR

V

V

R


l%shdldrlu 2'7

wdf,dal wmlsrKh ksÍCIKh lsÍu'

§ma;su;a ysre t<shg ;, o¾mKhlawe,a,Sfuka Tfí mka;s ldurhg fydaúoHd.drhg fyda l=vd Èla isÿrla yrydwdf,dal loïnhla fhduq l< yels h'ùÿre m%siauhla fïihla u; ;nd iqÿmdg ;srhla tA wdikakfha iDcqj;nkak ^ rEmh 2'35 &' rEmfha fmkajd we;s mßÈ mrdj¾;s; wdf,dal loïnh m%siauh fj; fhduq lrkak' m%siauhu; b;d §ma;su;a wdf,dal loïnhla ,efnk ;=re ;, o¾mKfha ia:dkhiSre udre lrkak' j¾Kdj,sh meyeÈ,s j fmfkk f;la ;srfha ia:dkh oiSre udre lrkak'

2'34 rEmh - ksõgka ;eáh

2'36 rEmh - j¾Kixfhdca kh

m%d:ñl yd oaú;Shslj¾K'

´kEu j¾K folla ñY% lsÍfuka iqÿ wdf,dalh ,efí kï tu j¾K fol fmdÿfõ wkqmQrl j¾K f,i ye¢kafõ' ksoiqka( ks,a yd ly wkqmQrl j¾K fõ' fï wkqj" ks,a iy ly" r;= iy uhqr ks,a" fld< iy uefckagdwkqmQrl j¾K fõ 2'36 rEmh&'

m%d:ñl yd oaú;Shsl wdf,dal j¾K

r;=" fld< yd ks,a m%d:ñl wdf,dal j¾K f,i ye¢ka fõ' Bg fya;= ù we;af;a

(i) fjk;a wdf,dal j¾K ñY% lsÍfuka fï j¾K idÞ.; fkdyels ùu;a"

(ii) fuu wdf,dal j¾K ;=k muKla ñY% lsÍfuka iqÿ wdf,dalh ,nd .; yels ùu;ah'

r;= + fld< + ks,a iqÿ wdf,dalh'

wdf,dal j¾Khla idÞ .; yelsh'r;= + fld< lyfld< + ks,a uhqr ks,ar;= + ks,a uefckagd

2'35 rEmh

;, o¾mKh

iQ¾hhd

ms%iauh

;srh

fïih

wdOdrlh

fudagrhl wËhg fuf,i j¾K fhdÞ.;a ;eáhl flakaøh iú lrkak' bkamiq fudagrh lrljkak' túg Tng j¾K fjka fjka j fkdfmkS" j¾K ñY% ù iqÿ meye;s ;eáhla olakg ,efnkq we;' fuhska fmkS hkafka iqÿ wdf,dalh j¾K 7 lska iukaú; njhs'

oaú;Shsl j¾K ( ´kE u m%d:ñl wdf,dal j¾K folla ñY% lsÍfuka oaú;Shsl


iQ¾hhdf.ka ,efnk iqÿ wdf,dalhj¾;kh

jeys ìxÿjR

R

V

VwNHka;rmrdj¾;kh

l%shdldrlu 2'8

idÞ.kq ,nk foaÿkakla ksÍCIKh lsÍu

mksÜgqjlg c,h mqrjd.kak' fuu c,h ;=<g fldyq ,Kqjla oukak'c,fha fmÕ=Kq fldyq ,Kqj mksÜgqfjka bj;g .kak' iQ¾hhd msysgk ÈYdjg úreoaO ÈYdjg uqyqK ,d isg .kak' ±ka fldyq ,Kqj fõ.fhka .ikak' my;g jEiafik l=vd c, ìxÿ w;r Tng foaÿkakla ±l.; yels h

foaÿkak

Tn lsishï Èfkl foaÿkakla ksÍlaIKh lr ;sfí o@ jeiaila we;s wjia:djl iQ¾hdf,dalh ;sfí kï foaÿkakla ±l .; yels h' tA i|yd Tn ysreg msgq md wyi foi ne,sh hq;=h' fï wkqj Woh ld,fha foaÿkakla ±lsh yelafla niakdysr ÈYdfõ h' ijia ld,fha§ kï kef.kysr ÈYdfõ h'

iQ¾hdf,dalh wyfia we;s jeys ìxÿjlg we;=`M jk úg j¾;kh fõ' ^úr,udOHhl isg .yK;r udOHhlg .uka lrhs&' fuys§ tu wdf,dalh wmlsrKhg Ndckh ù ix>gl y;lg fjka fõ' ksÍlaIlhl=f.a weig <Õdùug fmr" fuu wdf,dalh c, ìxÿj ;=< mrdj¾;khg ,la fõ'

2'37 rEmh - c, ìxÿjla yryd wdf,dalh .uka lrk whqre

'l%shdldrlu 2'9

Tfí uqLhg c,h mqrjd .kak' bkamiq iQ¾hhd msysgk ÈYdjg msgqmd isg.kak' ±ka uqLfha we;s c,h úisÍ hk fia msôkak' úys§ hk c, ìxÿ u;foaÿkakla fmfkkafka ±hss ksÍCIKh lrkak'


2'39 rEmh - W;a;, yd wj;, ldpj, m%Odk kdNs ,laIHhka

W;a;, ldp wNsidÍ (convergent) ldp hkqfjka o, wj;, ldp wmidÍ(divergent) ldp hkqfjka o y÷kajhs' ldphl j¾;k mDIaG foflys jl%;d flakaø hd lrk f¾Ldj tys m%Odk wlaIh hs' W;a;, ldphl m%Odk wlaIhg ióm j yd iudka;r j .uka lrk wdf,dal lsrK W;a;, ldph ;=<ska j¾;kh ùfuka miq we;=<g keó .uka lrhs' tAjd wNsirKh ù uqK .efik ,laIHh m%Odk kdNsh(focus) fõ' fuh ;d;aúl h' th F f,i kïlrkq ,efí' ldpfha j¾;k mDIaGj, uOH ,laIHh tys m%ldY flakaøh (optical centre) C fõ' m%ldY flakaøfha isg m%Odk kdNshg we;s ÿr ldpfha kdNs ÿr (focal length) f,i ye¢kafõ' fuys w.h fok ,o ldphla i|yd ksh; w.hls.

m%Odk wlaIhg ióm j yd iudka;r j wj;, ldphla ;=<ska .uka lrk wdf,dal lsrK j¾;kfhkaa miq wmidÍ j .uka lrhs' wj;, ldphl m%Odk kdNsh jkafka lsrK j¾;kfhka miq wmidÍ j tkakd fia fmfkk ,laIHh hs' ^2'39 rEmh &' fuu kdNsh w;d;aúl h'

l%shdldrlu 2'11

F = m%Odk kdNshC = m%ldY flakaøhCF = kdNSh ÿr (f)

wj;, ldph

CF

;=kS ldp, ldp ùÿrej,ska fyda mdroDYH ma,diaálaj,ska idÞ we;' W;a;, ldpj, ueo jeä >klulska hqla; jk w;r Þrh ;=kS j idÞ we;' wj;, ldpfha Þrh jeä >klulska hqla; h rEmh 2'38 &.

2'4 ldpj,ska iEfok m%;sìïn uÕska m%ldY WmlrK k s¾udKh lsÍu

W;;a , ldph

mO% dk wlIa h

C F

2'38 (a) rEmh - ;=kS ldp j¾. lsysmhla

oùa w- j;,ldph (bi con-cave lens )

;, W;a;, ldph (plano convex lens )

;, wj;, ldph ( plano concave lens )

oaù W;a;, ldph( bi convex lens )

2'38 (b) rEmh

ldphlg fome;af;kau wdf,dalh m;s; ùj¾;kh ùfï yelshdj we;s ksid kEu ldphl, tys fomi m%Odk wlaIh u; m%Odk kdNs ,laIH folla y`ÿkd.; yels h.;jo tu ,laIH ldpfha isg iu ÿßka msysghs.

F FFF CC


ldp yryd wdf,dal j¾;kh ksÍCIKh lsÍu W;a;, ldphla" wj;, ldphla yd iqÿ lvÞishla .kak' §ma;su;a iQ¾hd f,dalh mj;sk wjia:djl mka;s ldurfhka msg; isg W;a;, ldphla fmdf<djg iudka;r j hï Wilska w,a,df.k Bg my<ska 2'40 rEmfha ±lafjk mßÈ lvÞish ;nkak' b;du;a §ma;su;a wdf,dal ;s;la lvÞish u; ,efnk f;la ldpfha ia:dkh iSre udre lrkak'

fuys§ W;a;, ldph iSre udre lrkúg tys tla wjia:djl b;d §ma;su;a wdf,dal ;s;la lvÞish u; wNsirKh fõ'fuh W;a;, ldpfha m%Odk kdNsh hs'tfy;a wj;, ldph uÕska lvÞish u;wdf,dalh wmirKh jk nj fmfka'wj;, ldph Ndú; lrñka fuuls%hdldrlu kej; lrkak' lvÞish u;wvq §ma;shlska hq;a jvd úYd, wdf,daljD;a;hla Tng ±lsh yels h'

2'41 rEmh - W;a;, ldp i|yd jQ úfYaIs; lsrK

mO% dk wlIa h mO% dk wlIa h

C CC

F F

ldpj, kdNSh ÿr msßlaiSu2'40 rEmh - W;a;, yd wj;,

ldpj,ska ,efnk m%;sìïnj, msysàu" úYd,;ajh iy iajNdjh mßudKhgwe¢ lsrK rEm igyka uÕska ksrEmKh l< yels h' fï i|yd úfYaI iïu; lsrK lsysmhla Ndú; flf¾'

(i) W;a;, ldp

lsrK rEm ks¾udKh lsÍu i|yd Ndú; lrk úfYaIs; lsrK'

1' m%ldY flakaøh yryd .uka lrk kE u lsrKhla j¾;kh fkd ù È.g u th ;=<ska .uka lrhs 2.41 a rEmh&'

2' W;a;, ldphl m%Odk wlaIhg ióm j yd iudka;rj .uka .kakd lsrKhla j¾;kfhka miq F yryd .uka lrhs ^2.41 b rEmh&.

3' W;a;, ldphl F yryd tk lsrKh ldph ;=<ska j¾;kfhka miq msgjkafka m%Odk wlaIhg iudka;r j h 2.41 c rEmh&'

W;a;, ldph

wj;, ldph

( a ) ( b ) ( c )


wj;, ldphla uÕska iEfok m%;sìïn ks¾udKh lSÍu

wj;, ldphlska ,efnk m%;sìïnhl msysàu" m%udKh ks¾Kh lsÍu i|yd 2'43 d& rEmfha mßÈ mßudKhg we¢ lsrK rEm igykla Ndú; l< yels fõ' tys wj;, ldphlska ,efnk m%;sìïnh iEu úg u w;d;aúl h" l=vd h" Wvql=re h' m%;sìïnh msysgkafka jia;=j ;snQ me;af;a u h 2'43 rEmh&'

2'43 rEm - wj;, ldpj, úfYaIs; lsrK(a,b,c)

lsrK rEm igykl § m%;sìïnh msysá ia:dkh" úYd,;ajh yd iajNdjh ,nd .ekSu i|yd by; lS úfYaI lsrK ;=fkka wju jYfhka folla fhdÞ .;yels h'

W;a;, ldphla uÕska iEfok m%;sìïnhl msysàu" m%udKh" úYd,;ajh yd iajNdjh ks¾Kh lsÍu

kdNsh ÿr 4 cm jQ W;a;, ldphla bÈßmsg 6cm wE;ska 3cm Wi jia;=jla ;nd we;'

fuh 2'42 rEmfha mßÈ mßudKhg we¢ lsrK rEm igykla wdY%fhka fmkaúhyels h' fuys § iEfok m%;sìïnh ;d;aúl nj;a úYd, yd hál=re jk nj;a Tng fmfkkq we;'

wj;, ldp flfrys iïu; lsrK

1' m%ldY flakaøh yryd tk lsrK wj;, ldphla ;=<ska j¾;kh fkdù È.gu th ;=<ska .uka lrhs 2'43 a rEmh&'

2' m%Odk wCIhg ióm j yd iudka;r j .uka lrk lsrKhla wmirKh jkafka th j¾;kfhka miq kdNsfha isg tkakdla fia fmfkk f,isks ^2'43 b rEmh&'

3. kdNsh t,af,a tk lsrK j¾;kfhka miq m%Odk wlaIhg iudka;rj .uka lrhs ^2'43 c rEmh&.

2'42 rEmh - W;a;, ldphlskam;% ìs ïnhla we;s jk whrq e

jia;=j'

m;% ìs ïnh

CF

C FFC F F

( b ) ( c )( a )

O FI

C


c& jia;=j 2 F yd F w;r

m%;sìïnh ;d;aúl" hál=re" úYd,

ji;a j= g úreoOa me;fa ;a 2F tmás ka

ji;a j= 2F g wE;ks a(e)

m%;sìïnh ;d;aúl" hál=re" l=vd" jia;=jg

úreoOa me;fa ;a

2'44 rEmh - jia;=j msysgk ia:dkh wkqj W;a;,ldphl m%;sìïnfha iajNdjh fjkia jk whqre

l%shdldrlu 2'12

W;a;, ldp u`.ska iEfok m%;sìïn

my; i`oyka o;a; fhdÞf.k mßudKhg lsrK rEm igyka we`o iEu wjia:djl § u ,efnk m%;sìïnj, msysàu" úYd,;ajh" m%udKh yd iajNdjh

úia;r lrkak' ish¨ u lsrK rEm igyka i|yd W;a;, ldpfha kdNSh ÿr 2cm

f,i o jia;=fõ Wi 2cm f,i o fhdÞ.kak'

1' jia;= ÿr 5 cm 2F g jvd jeä& 4' jia;= ÿr 2 cm Fg iudk&

2' jia;= ÿr 4 cm 2Fg iudk& 5' jia;= ÿr 1 cm Fg wvq&

3' jia;= ÿr 3 cm Fg yd 2F w;r&

(F) jia;=j wkka;fha"

m%;sìïnh ;d;aúl" hál=re" l=vd" jia;=jg

úreoOa me;fa ;a

(d) jia;=j 2 u;"F

m%;sìïnh ;d;aúl" hál=re" jia;=jg m%udKfhkaiudk jia;=jg úreoaO me;af;a 2F u;

(b) jia;=j u; F

m%;sìïnh wkk;a fha

(a)

m;% ìs ïnh w;d;úa l" Wvql=re" úYd," jia;=j me;af;a

ji;a j= F yd C

3OF L

F

I

F2F F 2F

I

F

FF 2F

2F FO

I2F

F

F2FO

IF 2F

O2F F

2.43 (d) rEmh - wj;, ldphlska ,efnk m%;sìïn'

O F I

OI

- jia;=j

m%;sìïnh-

w;r"


2'45 rEmh

W;a;, ldphlska úYd,s; Wvql=rem%;sìïnhla ,nd.ekSu

l%shdldrlu 2'14

W;a;, ldphla ir, wKaùCIhla f,i Ndú; lsÍu' >klï lïìhla fhdÞ idÞ.;a wdOdrlhla u; 2'46 rEmfha mßÈ W;a;, ldphla ;nkak' úYd, lr ne,sh hq;= wl=re iys; lvÞish ldph;a wdOdrlfha mdoh;a w;r ;nkak' ldphg by<ska neÆ úg lvÞisfha we;s wl=re úYd, ù fmfkkq we;' wl=rej, b;d meyeÈ,s m%;sìïn ,nd .ekSu i|yd lvÞish iSre udre lsÍfuka mq¿jk'

l%shdldrlu 2'13

W;a;, ldphlska iEfok m%;sìïn ksÍCIKh lsÍu'

iqÿ ì;a;shla bÈßfha Bg ;rula wE;ska bámkaoula o,ajkak' bkamiq ì;a;sh iy bámkaou w;ßka W;a;, ldphla r|jkak' bámkaoï ±,af,ys meyeÈ,s m%;sìïnhla ,efnk ;=re ldph iSre udre lrkak'

ldpfha isg jia;=jg bámkaoug& we;s ÿr iy ldpfha isg iy m%;sìïnhg we;s ÿr;a ukskak' jia; = ÿr iy m%;sìïn ÿr fjkia lrñka fuu l%shdldrlu kej; kej;; a lrkak' m%;sM, 2'44 rEmfha lsrK .uka u`. iu. ikaikaokh lrkak'

2'47 rEmh - W;a;, ldphlska úYd,s; Wvql=re w;d;aúl m%;sìïnhla ,efnkwhqre

m%ldY WmlrK

1' ir, wKaùlaIh'

W;a;, ldphla l=vd foa f,dl= lr ne,Sug fhdÞ.kq ,efí' th w;a ldphla f,i;a úYd,l ldphla f,i;a ir, wKaùCIhla f,i;a y÷kajhs' 2'46 yd 2'47 rEm&

2'46 rEmh

m;% ìs ïnh

w;d;úa lWvlq r= eúYd,

jia;=j F yd Cw;r

m;% ìs ïh

F F

C

wei


2'48 rEmh - wKaùlaIfha ldp yd m%;sìïn msysàu

F-o wjfkf;a

kdNsh

F-e Wmfkf;a

kdNsh

I -1 wjfk; ksid iEfok

hál=re" ;d;aúl" úYd, m%;sìïnh

I -2

Wmfk; kis d iEfok wjidk m%;sìïnh

2' ixhqla; wKaùCIh (compound microscope)

úYd,kh jeä lÍs u i|yd ixhlq ;a wKùa lIa hl ldp folla fhdÞ we;'ji;a j= wdikka fha we;s m<uq ldphg wjfk; hehs lhs kq ,efí' wei wdikka fha ;fs nk fojeks ldph Wmfk; f,i ye¢kfa õ' ldp fofla ixfhdca kfhka iEfok wjidk m;% ìs ïnh ji;a j= g idfmla Ia j hálr= e úYd,;s w;d;úa l m;% ìs ïnhl's

jeäÿr ±Kqugwjfk; fhdÞ.kq ,nkafka I kï jQ ;d;aúl hál=re m%;sìïnhla ,nd.ekSug h' 1

fï i|yd jia;=j ;eìh hq;af;a wjfkf;a kdNsh jQ F yd 2F w;r h' Wmfk; 0 0

fhdÞ .kafka m<uq m%;sìïnh jQ L "úYd, lr ne,Sug h' th úYd,l ldphla 1

f,i l%shd lrhs' tA wkqj I kï jQ m<uq m%;sìïnh Wmfk;g jia;=jla f,i l%shd 1

lrhs' th Wmfk; yd F kdNsh w;r ia:dk.; úh hq;=h' I kï jQ Wmfkf;ka e 2

iEfok wjidk m%;sìïnh I ys w;d;aúl Wvql=re úYd, m%;sìïnhla úh hq;= h' 1

ldp fofla ixfhdackfhka iEfok I kï jQ wjidk m%;sìïnh jia;=jg idfmalaI 2

j hál=re úYd, m%;sìïnhls' idudkH iSre udrefõ § th jia;=jg wdikak ia:dkhl msysghs' 2'48 rEmh&

ixhqla; wKaùlaIfha úúO fldgia

1' wKaùCI mqjrej

2' wdf,dal Odrdj

3' ;=vqlv

4' wjfk;

5' wKaùCI ngh

6' o¾mKh

7' o, iSre udre bial=remamqj

8' la,smh

9' Wmfk;

10' ishqï iSreudre bial=remamq ysi

9

1

2

3

4

5

6

7

8

10

I2 F0 Fe

I1 Fe

0

wjfk; kdNÿs r flá h'&F0Wmfk; kdNÿs r o.s = h&Fe

1 yd 2 wjidk m;% ìs ïNh iEfok i:a dkh fidhd .ekuS i|yd w¢kq ,nk úfYIa ;s f¾Ld 2'49 rEmfha ±lfa õ'

2

1

2'49 rEmh - ixhqla; wKaùlaIh


Wmfk; úYd,l ldphla f,i lh% s d lrkflá kdNhS ÿrla Fe we;s wNis dÍ ldphl's wjidk m;% ìs ïnh ji;a j= fuka u wkk;a fha mys gs k f,i irS e udre lÍs u idudkH ißs ; h' Wmfkf;a mO% dk kdNhs jQ Fe u; ;d;úa l ji;a j= la f,i I kï m<uq ;d;úa l m;% ìs ïnh i:a dk .; lÍs fuka fuh imrq d.kq ,efí' weig <Õdjk lrs K wkk;a fha we;s wjidk m;% ìs ïnfha igs tkka dla fia fmfkk iudk;a r lrs K fõ'

wjfk; úYd, újrhla yd §¾> kdNSh ÿrla Fo we;s wNsidÍ ldphls' wE; msysá m%Njhlska yels;dla wdf,dalh tl;= lr .ekSug úYd, újrhg yelshdjla we;' leurdjl l%shdldÍ;ajhg iudk j wE; we;s jia;=jl ;d;aúl" hál=re m%;sìïnhla wjfk; úiska we;s lrhs'

(

2'52 rEmh - ms%iau fofk;sh

wjfk;

Wmfk;

4' fofk;hs (binocular)

klIa ;% ¥f¾lIa hl È. jeä ùu;"a thks a wjidk jYfhka ,efnk m;% ìs ïnhhálr= e ùu;a tu ¥f¾CIfha wjdis s fõ' fuu .eg¨ j uÕyrjd .ekuS g idÞwe;s fofk;fs ha mis% ua folla fhdÞf.k we; ^2'52 rEmh&' wjfk; yd Wmfk;ldp w;r tu mis% ua fol mys às fuk"a wdf,dla h k<h ;<= ;k= a jrla .uka lrjkq,efí' tuÕks a WmlrKfha È. wvq lÍs ula iÿs fõ' Bg wu;r j thks a ,efnkwjidk m;% ìs ïnh Wvlq r= e tlla fõ' mis% ua yryd iÿs jk m¾Q K wNHk;a rmrdj¾;kh fuys § mf% hdca khg .efk'a

2'51 rEmh - klaI;% ÿf¾laIh

wjfk;

3' klaI;% ÿf¾laIh'(astronomical telescope)

fuh hál=re" w;d;aúl m%;sìïnhla wkka;fha ,nd .ekSug wNsidÍ ldp folla fhdÞ idok ,o j¾;k ÿf¾laIhls 2'50 yd 2'51 remh&'

I kñka ,l=Kq lr we;s fuu m%;sìïnh tys m%Odk kdNsh jQ F u; msysghs' fuu o

m%;sìïnh l=vd jQjls'

klIa ;% ¥f¾lIa hg jvd mis% ua fofk;hs la Ndú;fha we;s jdis

i. Wvlq r= e m;% ìs ïnhla ,eîu'

ii. WmlrKh lv= d kis d myifq jka mßyrKh l< yelùs u'

iii. weia folu fhdod.kka d kis d ;us% dK o¾Ykhla ,nd.; yelùs u'

2'50 rEmh - iudka;r lsrK weig <Õd fõ

ÿr we;sjia;=jlskatk iudka;rlsrK

wjfk; ^È. f0

újrh úYd,&Wmfk;flá f

I

f0 fe

F0

F0

Fe Fe

I1

e

jeäÿr ±Kqug


5' lÞ ml% fa Ima h (slide projector)

m%lafIamhl wj;, o¾mKhla yd úÿ,s mykla uÕska jia;=j §ma;su;aflf¾' úÿ,s myk wj;, o¾mKfha jl%;d flakaøh u; msysgk fia ;nd we;af;a wdf,dal lsrK kej; jrla uq,a ud¾.fha u .uka lrùu i|yd h' §ma;su;a mska;+rhla ,nd §u i|yd ix>kSldrl ldphla fhdÞ f.k we;' th idudkHfhka 2'53 rEmfha olajd we;s mßÈ ;,-W;a;, ldp follska idÞ we;' wdf,dalh ;srh foig wNsirKh jk ksid lodj fyda fiahd mgh §ma;su;aj yd iudldr j m%§ma; fõ' fiahd mgh fyda lodj fyda uÕska úisÍ hk wdf,dalh wNsidÍ ^W;a;,& ldphla jQ m%lafIam ldphla uÕska ;srh u;g kdNs.; fõ'

,efnk m%;sìïnh ;d;aúl" Wvql=re" úYd, tlla ùu i|yd fiahd mgh fyda lodj fyda m%lafIam ldpfha f yd 2f w;r ;nd we;' fiahd mgh fyda lodj fyda m%lafIamh ;=< Wvq hál=re jk fia we;=¿ lrkafka m%;sìïnh ;srh u; ksis f,i Wvql=re j fmkSu i|yd h 2'53 rEmh&'

leurdj (camera)

leurd ;=< we;s wdf,dal ixfõ§ fiahd mghla u; ;d;aúl" hál=re l=vd m%;sìïnhla ,nd .ekSu i|yd wNsidÍ ldphla iuyr úg ldp lsysmhl ixfhdackhla& fhdÞf.k we;' idudkH leurdjl ±lsh yels jeo.;a fldgia lsysmhla 2'55 rEmfhka ±lafõ'

;d;úa lWvlq r= eúYd,m;% ìs ïnh

;rs h

wj;, o¾mKh ix>kSldrl ldph

fiha dmgh

m%lafIam ldph

2'53 rEmh - lod m%lafIamh

2'54 rEmh - leurdj

c

újr uqÿjwu;r ldp

mg, ,nd.kka d îr¿j

mg, tf;kflfjkhs

mvS k ;yvjq

fiahd mg,h

mg, leiÜgqjkdN.s ;uoq oa

md% Örh

;drd uKav,h

wNsidÍ ldph

2'55 rEmh - leurd ldp uÕska m%;sìïnhla,efnk whrq e

jia;=j

ixjdrlh


fiahd mg,h ( (photo film) leiÜgqjlska pl%hl wdOdrfhka ,nd .kakd îr¿jla u; we;s ;=kS È. ;Srejls' msgqmi we;s mSvk ;yvqjl wdOdrfhka th tu ia:dkfha È.yeÍ mj;S' tys wdf,dal ixfõ§ mDIaGh ldphg uqyqK ,d ;sfnk fia ilia lr we;' úúO Ndú;ùïj,g wkql+, j fjkia ixfõoS;djla we;s lrhs'

ixjdrlh ( (shutter) PdhdrEmhla .kakd úg ixjdrlh ál fõ,djlg újD; ù leurdj ;=<g we;=¿ jk wdf,dalh fiahd mg,h u; ksrdjrKh lrhs' iuyr úg fuu ksrdjrK ld,h fjkia jkakg mq¿jk' th fokq ,nkafka ;;amrhl Nd. f,i h' tkï ;;amr 1$1000" 1$60 hkd§ jYfhks' jeä fõ.fhka p,kh jk jia;=j,g wvq ksrdjrK ld,hla fhÈh hq;= h'

újrh ( ixjdrlh újD; l< úg iEfok isÿf¾ újrfha& m%udKh wkqj md,kh jk wdf,dalfhka fiahd mg,h u; m;s; jk m%;sìïnfha §ma;su;a nj ;SrKh fõ' iuyr tAjdfha újr w÷re o¾Ykj, § úYd, lsÍug;a wjYH mßÈ l=vd lsÍug;a mq¿jk' újrh f- wxlh kñka ,l=Kq l< yel' f- wxlh 8la jk úg újrfha úIalïNh ldpfha kdNSh ÿfrka 1$8 ls' fï wkqj f- wxlh jeä jk úg újrh l=vd fõ'

6' Wysia m%lafIamlh (Overhead Projector)

fm%alaIlhska iuQyhlg m%;sìïn úoyd ±laùu i|yd Wysia m%lafIamlh fhdÞ.kS' Wysia m%lafIamlh wjYHfhk a u b;d §m;a us ; a t<hs l a úyÿs jk úÿ, s mykl a we; súYd, fmÜáhlks a yd th iis ,s a lÍs ug fhdÞ.kka d úÿ, s mxldjlks a o iukúa ; h' fmÜáfh a by< uKQ ; ±ä ùÿre ;yvjq lks a kus lr we; s w;r Bg by<ks a we; s W;;a , ldph iudk;a r wdf,dla loïnhl a ,nd.ekuS i`oyd irS e udre l< yel s h' fmÜáhg Wäk a we;s È. ndyqfõ msysgd we;s ;, o¾mKh uÕska tu wdf,dal loïnh by<g fhduq lrkq fjkqjg kej; bÈßhg fhduq l< yels h'

úksúo fmfkk >k mg,hl igyka lrk ,o oE (transparencies) úysÞ ±laùu i|yd fõosldj u; ;nkq ,efí' túg úÿ,s myfkka ksl=;a jk wdf,dalh lvÞish yryd f.dia ;, o¾mKhg <Õd ùfuka ;srh u; úoyd ±laùula we;s fõ' bÈßm;a lrkakd lvÞish foi n,d f;dr;=re úia;r lroa§" fm%alaIlhdg o tys we;=<;a foa bÈßmi we;s ;srh foi n,d ±l.; yels h'

ilikbial=remamqj

ùÿre ;yvjq

;, o¾mKh

2'56 rEmh - Wysiaml% fa Ima h


wNHdi

1' úYd, ;, o¾mKhl 10 m bÈßfhka ñksfila keÕsg isà' Tyq;a Ty qf.am%;sìïnh;a w;r we;s ÿr 5 m ùug Tyq fldmuK ÿrla weúÈh hq;= o @

2' ;, o¾mKhlska ,efnk m%;sìïnj, mj;sk ,laIK 5la olajkak'

3' my; i|yka foa wj;, o¾mK yd W;a;, o¾mK hk fofldgig fnod olajkak' /jq, lemSfï § Ndú;d lrk lKakdäh" fudag¾ r:hl m%Odk ,dïmq o¾mKh" fidaÈis wdf,dal ,dïmqj (search light) ßheÿre lkakdäh" oka; ffjoHjrekaa uqLh mÍlaId lrk o¾mKh" úÿ,s mkaoï lkakdäh" m%lafIaml ,dïmq o¾mKh" ;Ügq fofla nihl ;rmamq fmf<ys we;s o¾mKh" uqyqK yev.ekaùfï § fhdÞ.kakd o¾mKh (make- up mirror)mrdj¾;k ¥f¾laIhl we;s o¾mKh" idmamq wdrlaIl lkakdäh'

4' (a) kdNSh ÿr 4 cm jQ wj;, o¾mKhl 5 cm bÈßfhka jia;=jla ;nd we;' tys Wi 3 cm ls' tu jia;=fjys m%;sìïnhla ,efnk whqre ±laùug lsrK rEm igykla w¢kak'

(b) tys § ,efnk m%;sìïnh;a" (i) ÿr (ii) m%udKh (iii) iajNdjh hk lreKq ms<sn|j;a úia;r lrkak'

5' msyskqï ;gdlhla 3 cm .eUqre nj Èi fa õ' c,fha j¾;k wxlh 4/3 kï msyskqï ;gdlfha i;H .eUqr fidhkak'

6' 4 cm Wi j i a;=jla kdNh ÿr 5 cm jQ W;a;, ldphl 15 cm bÈßfhka ;nd we;' iïmQ¾K m%udKhg fyda mßudKhlg fyda wkqj m%ia;dr lvÞishl lsrK rEm igykla we| m%;sìïnh msysá ia:dkh" m%udKh yd iajNdjh ks¾Kh lrkak'

7' (a) 2'57 rEmhg wkqj(i) m;k fldaKh(ii) j¾;k fldaKh hk fldaKj,

w.hka ,shkak(iii) X kï øjHfha j¾;k wxlh

.Kkh lrkak'

8' W;a;, ldphlska my; ±lafjk whqßka m%;sìïn ,nd .ekSug jia;=jla ;eìh hq;= ia:dk kï lrkak'

(i) úYd," Wvql=re" w;d;aúl

(ii) ;d;aúl yd jia;=jg jvd l=vd

(iii) ;d;aúl yd jia;=jg jvd úYd,

(iv) ;d;aúl yd jia;=fõ m%udKhg iudk

350X øjHh

2'57 rEmh

250

jd;h


9' (a) klaI;% ¥f¾laIhl wjfk; m%;sìïnhla idokafka lskï ia:dkhl o @

(b) Wmfkf;ka isÿ jk ld¾hh l=ula o @

10' klaI;% ¥f¾laIhlg jvd m%siau fofk;shl we;s jdis ;=kla ,shkak'

11' j¾Kdj,shl we;s j¾K ixfhdackh lsÍfuka iqÿ wdf,dalh ,nd.; yels nj

fmkajkafka flfia o@

12' iDcqfldaKdi%dldr ùÿre l=Üáhla ;=<g wdf,dal lsrKhla we;=¿ùu fuu rEm igyfkka 2'58 rEmh& ±lafõ'

(a) rEmh msgm;a lrf.k" wdf,dal lsrKh we;=¿ jk ,CIHh u; wNs,ïnh w`Èkak'

(b) ùÿre l=Üáh ;=<g we;=¿ jk lsrKh yd bka msg;g hk lsrKfha rEmfha wdikak .uka u`. ksrEmKh lrkak'

13' w¾O jD;a;dldr ùÿre l=Üáhlg we;=¿ jk lsrK folla 2'59 rEmfha

±la fõ'

(a) fuu lsrK P iy Q ,CIHj, § fkdkeù .uka lrkafka wehs

(b) rEmh msgm;a lrf.k fuu lsrK fol O j,g <`.d jQ miqisÿ jk foa ±laùu i`oyd tu lsrKj, wdikak .uka u`. w`Èkak'^ùÿrej, wjê fldaKh 43° ls'&

ùÿre

jd;h

700300

P

O

Q

2'59 rEmh

2'58 rEmh


14' my; i|yka 2'60 iy 2'61 rEm msgm;a lrf.k" bkamiq j we;s jk lsrKud¾. iïmQ¾K lrkak'

15' rEm igyka msgm;a lrf.k" iEu rEmhl uwdf,dal lsrK W;a;, ldpfhka j¾;kh ù hk ud¾. iïmQ¾K lrkak' 2'62 rEmfha a, b, yd c

2'60 rEmh 450 2'61 rEmh

600

600

450

( a )

FP

F

F

F

F

( c )

( b )

2'62 rEmh

Chapter 2 Physics

Documents

Transcript of Chapter 2 Physics