1fkd,fha fnod u i|yd h'

;rx. yd tAjdfha fh1

fuu mdvu yeoEfuka miq j Tng"

;rx. W;amdokh" m%pdrKh yd ;rx.hl .=K"

m%Odk ;rx. wdldr" O ;rx. j." tuska we;s jk n,mE"

jks ;rx. m%pdrKh" jksfha ,dlaI l .=K iy O ix.S;

NdKav iqir lsu yd tys Nd;hka ms

fkd,fha fnod u i|yd h'2

1'1 ;rx. W;ma dokh" mp% drKh yd ;rx.hl .K=

l%shdldrlu 1'2

oHd.drfha we;s ia,skalshla iu;, mDIAGhla u; ;nkak' tys tla

fl

3fkd,fha fnod u i|yd h'

fuys jd; wxY=

fkd,fha fnod u i|yd h'4

1'5 rEmh - ;Shla ;rx.hla ksrEmKh lrk wdldrh

lmkh ksid B

5fkd,fha fnod u i|yd h'

;rx. wdhduh (wave length)

tl u msysu yd p,s; Ydj olajk wkqhd; wxY= foll mr;rh

wdhduh k f' fuh ;rx.hl imQK pl%hla ksrEmKh lrhs' ;rx.hla hkq

fujeks pl% .Kkdjlska iuka; jQjls' ;rx.hl ;rx. wdhduh ^,evd&

j,ska ykajkq ,ef' th uksk tAllh g (m) f'

ia;drh (amplitude)

uOHkH msysf isg wxY=jl is jk Wmrsu ia:dmkh tys ia;drh k

f' th uksk iu; tAllh o g (m) f'

ixLHd;h (frequency)

;;amrhl we;s jk lmk .Kk fyda ;;amr tll we;s jk mQK

pl% ixLHdj tu p,s;fha ixLHd;h (f) k f' ixLHd;h uksk tAllh yia h

(Hz). tla lmkhla we;s f tla mQK pl%hla we;s f'

;rx.hl f.h (speed of a wave)

;rx.hla tla ;;amrhl tys f.h hs ;rx.hl ;rx.

wdhduh ( " ixLHd;h yd f.h w;r inkaO;djh my;

ilrKfhka fokq ,ef'

V = f

fuh ;rx.hl f.h i|yd ilrKh hs'-1

f.h ukskq ,nk tAllh m s f'

i ksoiqk(

iu (- iriqf,a ixLHd;h = 512 Hz

;rx. wdhduh = 0.65 m

V = f

-1

= 512 0.65 = 332.8 m s

1-2 ;rx. j.

wdf,dalh" jksh jek s fndfyd a Yl;a s fYIa mp% drKh jkfa k a ;rx. wdldrfhk a

nj wm s k a okus 'q jk s ;rx. mp% drKhg udOHhl a wjYH jjq o iQ hhd yd

;drldj,ks a kls ;= a lrk wdf,dla yd ;dm Yl;a kS a m:fhk a f;dr wjldYh yryd

;rx. wdldrfhk a mDhg

fkd,fha fnod u i|yd h'6

1' hdka;%sl ;rx.

2' oHq;a pqnl ;rx.

;rx.

hdka;%sl ;rx.^m%pdrKhg udOHhla wjYH f& ^m%pdrKhg udOHhla wjYH fkdf'&

wkajdhdu ;rx.

oHq;a pqnl ;rx.

;Shla ;rx.

;rx. m%pdrKh jk udOH wkqj wm wjg mirfha we;s ;rx. m%Odk f,i

j. follg fnh yelsh'

hdka;s%l ;rx.

;rx.hla m%pdrKh u i|yd m:uh udOHhla wjYH jk ;rx. hdka;%sl

;rx. .Khg wh;a f' tA wkqj jks ;rx." N+ lmk ;rx. iy c, ;rx."

hdka;%sl ;rx. .Khg wh;a f'

jks ;rx.

ksiqkaf.a lgy~" i;=kaf.a kdo" r:jdykj, k

7fkd,fha fnod u i|yd h'

N+ lmk" .sks l msms" kdh hE" uqyqo hg w;ay ne,S ksid we;s jk

msms yd W,aldmd; wdh iqkd ;;a;ajhka we;s ug fya;= f'

oHq;a pqnl ;rx. (electro - magnetic waves)

c, ;rx.

ksi, c, nklg .,a leghla uQ g ;rx. we;s jk nj ka wms oksuq'

fjd c, wxY= lmkh jk Ydjg ,nl j .uka lrk ;Shla ;rx. f'

fkd.eUqre c, ;rx.

c, ;rx.hla fjr

ksrEmKh

1'7 rEmh - oHq;a pqnl ;rx.

Y

Z

E

E

B

B B B

X

fkd,fha fnod u i|yd h'8

X,Y,Z tlfklg wNs,n ;,

B - pqnl lafIa;%h

E - oHq;a lafIa;%h

oHq;a pqnl ;rx.j,g O ixLHd; mrdi yd ;rx. wdhdu we;' ta

wkqj tAjd O .=Kj,ska hqla; f' kj ;dlaIKfoh Wmfhda.S lrf.k

ksmojk O fuj, Nd;fha oHq;a pqnl ;rx. nyq,j Wmfhda.S lr.kS'

ffhda yd rEmjdyskS" iQCIu ;rx. Wka" wfOdarla; ;rx. Nd; jk leurd"

wNHjldY hdkd" ffjoH WmlrK ta i|yd ksoiqka lsysmhls'

O-X ;rx.h m%pdrKh jk Ydj

oHq;a pqnl ;rx.j,g fmd ,dlaIKsl .=K iuyrla my; laf'

ffhda yd rEmjdyskS ;rx.

fjd oH;q a pq nl ;rx. w;k a Yd,;u ;rx. wdhduh iy;s ;rx. f' fuu ;rx.

.j= k a , s rEmjdyks S lgh;q = iy cx.u rl:k lgh;q = i|yd fhd .k'S kHz mrdifh a

;rx. AM ^i;a dr uQ Pk& ffhd a ;rx. f' MHz mrdifh a ;rx. FM ^ixLHd;

uQPk& ffhda ;rx. f' rEmjdyskS ldY ;rx. o MHz mrdifha tAjd h'

iQlaIau ;rx. (micro waves)

oHq;a pqnl jKdj,sfha .=jka ,s iy rEmjdyskS ;rx. ixLHd; mrdihg jvd

by< ixLHd;hla we;s ;rx. iQlaIau ;rx. f' fjd ikaksfok yd fvd

WmlrKj, Nd; f' b;d uE; ld,Sk j fuu iQlaIau ;rx. Nd; jkafka

Wkaj, h ' tys iQlaIau ;rx. u`.ska wdydrh

;=< u ;dmh ksmojk ksid msis j" tfuka u fmdaIl ydksh wvq fkdjk m

ldhlaIu j wdydr msi.; yels h'

! ifm%aIKhg udOHhla wjYH ke;'

! tla ia:dkhl isg ;j;a ia:dkhlg Yla;sh ifm%aIKh lrhs'

! ;Shla ;rx. f'8 -1

! la;fha 3 10 m s f.hlska ir, fh j .uka lrhs'

! oHq;a yd pqnl .=K we;'

! mrdj;k yd j;k kshuj,g tl`. f'

! wdfrdamKhla rys;h'

iQlaIau ;rx. (microwave ovens)

O

(m)

1'8 rEmh - .= ;rx. wdhdu yd fl ixLHd; mrdij, isg fl ;rx. wdhdu iy je

ixLHd; mrdi olajd jk oHq;a pqnl ;rx.

9fkd,fha fnod u i|yd h'

wfOdarla; lsrK (Infrared rays)

ilQ Ia ua ;rx.j, ixLHd;hg jvd by< ixLHd;hlks a h;q a wfOdra l;a lrs K ;dm

lrs lj, we; s mO% dk lrs K j.h f' ;dmh ydk s f fuu lrs K mgs f' hul a

WKiq q f fuu lrs K thg wjfYdIa Kh f' iQ h ;dmfhk ajH r; a f wfOdra l;a lrs K tu jH u`.ks a wjfYdIa Kh lr.k'S wfOdra l;a ixf

leurdj," ri:a md,lj, yd ffjoH oHdf fuu lrs K mf% hdca khg .k'S

jksh .uka lrkafka wkajdhdu ;rx. f,i nj o" jksh we;s ug

lmkhla we;s h hq;= nj o" fuhg by; wms bf.k .;suq'

jeis iys; kj, wyi .s.=re fok y~ weiSug iaj,am fudfyd;lg

fmr ,s t

fkd,fha fnod u i|yd h'10

'mejreu 1

jeis iys; fkl ,s flu yd f.ru we;s lrk j,dl=KGa d

irdj

la; fmdmh

,s iemhqu

11fkd,fha fnod u i|yd h'

fodaxldrh'

uqyqfoa .eUqr uekSug" uqyq n;a jQ kej, iqkanqka fidhd.ekSug " h hg u;aiH

?ka fidhd.ekSug" h hg hk iueka hd;%dj,g ke .,amr yd fjk;a ndOl

u`. yeug" f;,a ks wkdjrKh lr.ekSug fodaxldrh Wmfhda.S lr.efkhs'

jks ;rx. mrdj;kh

l%shdldrlu 1'4

ldfnda ng fyda PVC ng folla fyda imhd

.kak' tAjd rEmfha lafjk m iudk

wdk;shlska ;sfnk fia iu;, mDIaGhla u;

;nkak' Bg ,nl j ;j;a ;srhla (C)

;nkak' A ys jhska lrk w;a Trf,daiqjla

;nd Byss nghg lk ;nd th iSre udre lrka

ijka fokak' tla wjia:djl Trf,daiqf

la la y~ fydka wefia' fuhg fya;=j A ys

Trf,daiqfjka ksl=;a jQ y~ re mDIaGfhka mrdj;kh B lrd me uhs'

.,a mj;hla fyda l.eghla fyda fj;g f.dia Bg ;rula wE;ska isg yQ

y`vla ke`.+ g" tu y`v ksl=;a iq fudfyd;lg miqj tu y`v kej; wefik

wdldrh Tn w;al ;sfnkakg mqjk' fuu ixisoah fodaxldrh (echo) f,i

yekaf' fodaxldrhg fya;=j jrla weiqKq Yoh wE;ska msys ndOlhl .e

mrdj;kh kej;;a wdmiq wmf.a lk fj; meKSuhs'

h Yohla wmg weiqKq g th wmf.a lk ;=< ;;amr 1$10 l muKl

ld,hla / mj;S' tuksid fodaxldrhla we;s ug k uq,a Yoh iy tys

mrdj;kh w;r ld,h ;;amr 1$10 lg jvd jeh hq;= h'

-1

jd;fha jks m%f.h } 330 m s k

;;amrhla ^1 s& ;=< jd;h ;=< jksh .uka lrk r } 330 m

1 $10 s ;=< jd;h ;=< jksh .uka lrk r } 330 1$10 = 33 m

f wkqj fmfkkafka fodaxldrh weiSug k mrdj;kh jQ jksh wm lrd

meKsh hq;af;a g 33 l .uklg miqj njhs'

tu ksid m%Njfha isg mrdj;k mDIaGhg

;sh hq;= wju r

uq,a Yofha ixfokh uelS hdug m%:u tys mrdj;s; Yoh wfma lk

fj; meKSfuka tlu Yoh lk ;=< > f,djla / ;sfnkakd fia fka'

fuu ixios a h m;% ks doh ^reverberation& f,i yekfa '

iuq g mDIGa j,ks a jkhs tla dldrj mrdj;kh jk w;r r mDIGa u.ks a tla dldrj

mrdj;kh fkdf' tnek aYd,djl ;;a s r ls fuk afodxa ldrh wv qlr .; yel s h'

ksia lk ixfjk jks ;rx.j, ixLHd; mrdih 20 Hz - 20"000 Hz

f' 20"000 Hz g jvd by< ixLHd;hla we;s ;rx. ksidg fkd weiqk o

iqkLhka jeks i;=kag wefia'20"000 Hz ixLHd;hg by< jks ;rx. w;sjks

;rx.(ulta sound) f,i yekaf'

33

2

=

.16 5

=

17 m ^wdikakj&

=

BA C

1'10 - rEmh'

fodaxldrh m%fhdackhg .ekSu

fkd,fha fnod u i|yd h'12

f i|yd k

WmlrKhla Nd; lrhs' thska w;sjks

;rx. ksl=;a l< g tAjd w< jia;=j u;

m;s; mrdj;k tk ;rx.h wdhlh

k WmlrKhl iajhxl%Sh j igyka f'

c,h ;=< jksfha f.h okakd neka

fodaxldrhg .; jQ ld,h uek .ekSfuka

kef isg jia;=jjg we;s r fih yels h

^rEmh 1'11&'

m%;sjksudkh (Echosounder)

jks ,dCIl

wm wjg mirfhka wefik y~ O h' wyi .=.=rk y~ ier h'

flu isyska y~ls' ms lgy~ r h' .eyekq lgy~ uD h' ix.S; iajr Wia

yd my;a h' f ish foa jksfha ,dlaI l .=K ksid we;s f'

jksfha m%Odk ,dCIl .=K ;=kls'

1' ;dr;dj (pitch)

2' yf ier (loudness)

3' jks .K= h (quality of sound)

f ,dlaI l .=K .ek wms uid n,uq'

;dr;dj

mejreu 3

iskudYd,d iy kdgHYd,d ;=< fodaxldrh we;s u je

13fkd,fha fnod u i|yd h'

jks m%Njhlska ksl=;a jk y~" wE;g h;a u weiSu wvq f' thg fya;=j jks

;rx.h .uka lrk r je jk g l%ufhka ;rx.fha ;SjDr;dj wvq u hs' yf

ier jks ;rx.fha ia;drh u; r|d mj;S' ia;drh je g yf ier o je

f'

jks .=Kh

1'14 rEmh - O jks ;rx. rgd

iriq,

jh,kS h

mhs dfkdja

yf ier

fnrhlg fiuka ;gq lrkak' kej; tu jdr .Kk u ;ka ;gq

lrkak' uq,a y~g jvd fojeks jr y~ ier h' lk fj; jks ;rx. u.ska f.k

tk Yla;s m%udKh u; yf ier r|d mj;S'

we we;s ;ka;=jla ;ka fmE g bka ksl=;a jk y~ ier h' ;ka

fm

fkd,fha fnod u i|yd h'14

ix.;S NdKva

ksid muKla fkd j i;=ka mjd ix.S;hg we lrk nj Tn okS' we;e glr= e,,a kfa .a kdoh mjd ix.;S hla fuka wmg wefik g th fl;r wdija dockl

o@ jdokfha lkg ys iajr rgdjla we;s l< yels O NdKav ksmoug

ksid iu;a we;' tAjd ix.S; NdKav k f'

1' lmkh jk jdhq l`oka iys;

2' lmkh jk ;ka;= iys;

3' lmkh jk mg, iys;

lmkh jk jdhq l`oka iys; ix.S; NdKav

"

'

;;a iys; NdKav

jh,Skh" uekav,Skh" nekafcdaj" is;drh" .sgdrh jeks ix.S; NdKav f i|yd

ksoiqka f'

f iEu NdKva hl u ;k= S oejfhka

;ekQ fmhla jekakla we;' th jks

fmaldj ^ sound box & k f' ;;a

fm

15fkd,fha fnod u i|yd h'

ix.S; NdKav iqir lsu

ix.;S NdKva hl a jdokh i|yd ija r kis s m kls ;= a jk wdldrhg tu

NdKavh ilia lsu 'iqir lsu' (tuning) k f' fuu iqir lsu tla tla

NdKavh wkqj fjkia f'

;;a NdKav iqir lssf tys we;s lj,ska kef`.k iajrfha ,dlaI l fjkia

lsfuka iqir lrkq ,ef' O iajrj, ;dr;d ix.S;{hskaf.a lkg yqre h' tA

ksid Tjqyq Y%jK ixfokhg wkqj ix.S; NdKavh iqir lr;s'

;;l ;dr;dj

1' ;f;ys yrialv j.M,h ^>klu&

2' lmkh jk fldgfiys . ^ iM, .&

3' wd;;sh hk lreKq u; r|d mj;S'

;;l IalNh je k ;dr;dj wvq h' wd;;sh je g ;dr;dj by< h'

. je g ;dr;dj wvq h' fujeks ;;a NdKavj, we;s ;;a O f,dayj,ska

ksujd we;' tfuka u tAjdfhys ;;a lsysmhla u fhd we;s w;r tu tla tla

;f;ys IalNh tlsfklg fjkia h' lmkh jk mg, iys; NdKav iqir

lrk whqre Tn l ;sf o@ .no m%foaYj, ux.,H W;aij wdfha ;a wjqre

ld,fha ;a rnka jhkq Tn l we;' tfuka u ` .dhkd lrkakka l=vd rndkla

jhk whqre o Tn l we;'

rndkl we;s mg,h fndfyda g t iuls' jdokhg fmr rndk

r;a lrkq ,ef' r;a lrk g mg,h he

fkd,fha fnod u i|yd h'16

wNHdi

1' Tnf.a mirfha isjk p,k idudkH p,k yd lmk f,i

,ehsia;= .; lrkak'

2' my; i|yka m%ldY y k ,l=K o je/ k ,l=K o fhdokak'

i. ksidg kE u ixLHd;hl Yo ;rx. wefia'

ii. w;sjks ;rx.j,ska ksid m%fhdack .kS'

ii. ffhda ;rx.j, oHq;a yd pqnl .=K we;'

iv. .eUqre uqyqfoa iqkd ;rx.j, ia;drh

wvq jk w;r fjr