विज्ञान तथा प्रविधि कक्षा ९

tf/fsf] sf/] df pTkGg tfksf sf/0fn] tf/fsf] aflx/L txdf /xs] f] Uof;F kmS' b} hfG5 . t;y{ pd]/
cg;' f/ tf/fsf] ;fOh klg j[l4 xFb' } hfG5 . k/' fgf tf/fx¿ /ftf] /ªsf xg' fsf ;fy} lgs} 7'nf
bl] vg] ePsfn] ltgLx¿nfO{ /]8 hfOG6 elgG5 . w/] } 7'nf tf/fx¿af6 aGg] /]8 hfOG6nfO{ /]8
;'k/ hfOG6 elgG5 . ;fgf tf/fx¿rflxF /]8 hfOG6 gaGg klg ;S5g\ .

w/] } k'/fgf tf/fx¿df aflx/L txsf] Uof;F kmS' b} hfbF f sg' } laGbd' f sf/] n] cfsif0{ f ug{ g;s]/
aflx/L tx lj:kmf]6 xG' 5 . o:tf] lj:kmf]6gnfO{ gf]ef elgG5 . w/] } zlStzfnL lj:kmf6] g eof]
eg] ;k' / gf]ef elgG5 . lj:kmf]6g x'bF f tf/fsf] aflx/L txdf ePsf] UofF; / w'nf] axd\ f08df
5l/G5 . tL UofF; / wn' fsf s0fx¿ ;ª\slnt eO{ k'gM csf{] ga] 'nf aG5 . aflx/L tx lj:kmf6] eP/
5'6\l6Pkl5 tf/fsf] sf/] dfq afsF L /xG5 . o;sf] eljZo tf/fsf] ;?' sf] lk08df e/ k5{ .

kf| ]6f]:6f/
tf/f

/]8 hfOG6

/8] ;'k/ hfOG6

gf]ef ;'k/ gf]ef
-/8] hfOG6sf] lk08 ;"os{ f] -/8] hfOG6sf] lk08 ;"o{sf] eGbf

eGbf sd_ w/] } u'0ff a9L_

AxfO6 8k{m Go'6«fg] tf/f ANofs xf]n
- tftf,] dw/' f] b]lvg]_ - Go'6f« ]goS' t rf“8f] rf8“ f] -cTolws v'Drg] jm| ddf w]/}

Ans] 8k{m 3'Dg_] u?' Tj an ePsf] lk08_
-AxfO6 8k{m lr;f] eO{ cbZ[ o aG5_
kN;/ lrq 12.4 tf/fsf] hLjgrjm|
lj1fg tyf k|ljlwM sIff ( -lg/Gt/ PS; /] kN;
197
5f]8\g] Go6' f« g]

-s_ olb tf/fsf] lk08 ;o" s{ f] eGbf sd ePdf lglZrt ;dokl5 Go'lSno/ km\ oh' g kl| j|mof
;dfKt eO{ k|sfz/lxt ;fgf] lk08sf ¿kdf /lx/xG5 . o;nfO{ AofNs 8\jfkm{ -black
dwarf_ elgG5 .

-v_ olb tf/fsf] lk08 ;"os{ f] lk08sf] xf/fxf/L 5 eg] sf/] df Gol' Sno/ k\mo'hg nfdf] ;do;Dd
rln/xG5 . To;}n] o;nfO{ xj\ fO6 8\jfkm{ -white dwarf_ elgG5 .

-u_ olb tf/fsf] lk08 ;"os{ f] lk08eGbf 1.4 b]lv 5 u'0ff;Dd ePsf sf/] vfFlbP/ Go6' «f]gdfq
ePsf] lk08df kl/jtg{ xG' 5, o;nfO{ Go6' f« ]g :6f/ elgG5 .

-3_ olb tf/fsf] lk08 ;"o{sf] lk08sf] 5 u'0ffeGbf a9L ePdf sf/] vl' Dro/ cTolws ;fgf] t/
cTolws vlF bnf] lk08 aG5 . o;sf] u?' Tjan olt w/] } x'G5 ls ks| fz klg o;af6 aflx/
lgl:sg ;Sb}g / cbi[ o lk08sf ¿kdf kl/0ft x'G5 . To;n} ] o;nfO{ sfnf] l5b| -black
hole_ elgG5 . tyflk o;n] lg/Gt/ PS; /] pT;hg{ ul//xg] s'/f j}1flgsx¿n] kQf
nufPsf 5g\ . o;n] jl/kl/sf cGo lk08x¿nfO{ klg cfsif{0f u/L cfkm"df ;dflxt ug{
;S5 .

ax| d\ f08;DaGwL j}1flgs tYox¿ (Scientific facts about the universe)

a|Xdf08sf] pTklQaf/] 7f]; kd| f0f geP tfklg xfn eO/x]sf] a|Xdf08sf] lj:tf/n] o;sf] pTklQ
Ps vflF bPsf] lk08sf] lj:kmf]6g cyf{t\ lau a]ªu\ -Big Bang_ af6 ;'? ePsf] xf] . ;g\ 1920 df
a]lNhog j}1flgs hfh] { nd6] / -Georges Lemaitre_ n] xfdf| ] cfsfzuª\uf -milkyway galaxy_ /
cGo sof}F tf/k'~hx¿ Ps csfa{ f6 6f9f uO/xs] f] tYo kQf nufPsf lyP . o; l;4fGtcg';f/
aX| df08sf] pTklQ cfheGbf sl/a 13.8 c/a jif{ klxn] ePsf] xf] . aX| df08df /xs] f Tff/f,
tf/fk~' hx¿n] o;sf] lk08sf] s]xL efu dfq cfu] 6]sf 5g\ . t;y{ ax| \df08 kbfy{ / pmhfa{ f6
ag]sf] 5 . a|Xdf08df s'g} klg lk08 l:y/ cj:yfdf 5}g . s'g} g s'g} ;fkI] f laGb'sf cfwf/df
lk08x¿ rfndf xG' 5g\ . rGbd| f k[YjLsf] jl/kl/ 3l' d/xFbf k[YjL ;"os{ f] jl/kl/ 3'ld/x]sf] xG' 5 .
;f]xL cjlwdf ;"o{ klg cfsfzuª\ufsf] sG] b| jl/kl/ 3'ld/x]sf] xG' 5 .

aX| df08df cgulGt tf/fk'~hx¿ 5g\ . cfsfzuª\ufaf6 glhs}sf] csf]{ tf/fk'~h PG8«f]d8] f
tf/fk'~h xf] . of] kY[ jLaf6 2.5 ks| fz jifs{ f] b'/Ldf /xs] f] 5 . tf/fk'~hdf ePsf tf/fx¿ ;a}
Pp6} pd/] sf xF'bg} g\ . cfsfzuª\ufsf] Ps 5p] df /x]sf] ;fo} {d08nsf] pTklQ 4.6 ca{ jif{ klxn]
ePsf] xf] . kY[ jLdf xfn;Dd kf| Kt ;ae} Gbf k/' fgf] kbfys{ f ¿kdf hs{g dl0fe -zircon crystal_
/x]sf] 5 . o;sf] pd/] nueu 4.4 ca{ jif{ lx;fa ul/Psf] 5 .

a|Xdf08df ljleGg tf/fx¿sf] ;dx" df kY[ jL h:t} cfsf/, ;fOh / xl] a6a] n hfg] df ePsf cGo
ux| x¿ klg kQf nfu]sf 5g\ . ;g\ 2020 sf] hgj/L 5 df kQf nfus] f] TOI 700 d ux| 8f/] f8f]
tf/fd08n -Dorado constellation_ df cjl:yt TOI 700 tf/fsf] kl/j|mdf u5{ . pSt u|x
kY[ jLaf6 101.4 k|sfz jifs{ f] b/' Ldf /xs] f] 5 . aX| df08nufot lj1fgsf ljleGg Ifq] df ul/Psf
vf]hx¿n] gofF gofF hfgsf/Lx¿ kQf nfUb} uPsf 5g\ .

198 lj1fg tyf kl| jlwM sIff (

ljrf/0fLo k|Zg M s] j1} flgs l;4fGtx¿ (scientific theories) ;do;fk]If kl/jtg{ xg' ;S5g\ <

sHdf]nhL -cosmology_ a|Xdf08sf] pTklQ / o;sf] ljsf;jm| d;DaGwL cWoog ug]{ lj1fg xf]
. aX| df08;DaGwL cWoogsf nflu ko| f]u x'g] k|ljlwsf] ljsf;j|md ;uF } gofF gofF tYox¿ kQf
nfUb} uPsf 5g\ . sg' } tYox¿ k/' fgf l;4fGt kl| t:yfkg ug]{ klg xG' 5g\ . pbfx/0fsf ¿kdf
;f}od{ 08naf/] kf| rLg lj1fgn] :yflkt u/]sf] k[YjLs]lGbt| l;4fGt -geocentric theory_ nfO{
cfwl' gs lj1fgsf] ;o" s{ ]lGb|t l;4fGt -heliocentric theory_ n] k|lt:yfkg u/s] f] lyof] . To:t}
;g\ 2006 eGbf klxn];Dd ;fo} d{ 08nsf] vufn] Lo lk08 od -pluto_ nfO{ klg ux| sf ¿kdf
dfGotf lbOPsf] lyof] . u|xsf af/]df ;g\ 2006 df tof/ kfl/Psf cfwf/x¿cg';f/ od u|xsf]
;"rLaf6 x6fOof] . t;y{ lj1fgsf ljleGg Ifq] x¿df gofF cWoog, vfh] tyf cg;' Gwfg lg/Gt/
rln/xg] ePsfn] lj1fg rnfodfg xG' 5 .

a|x\df08sf] eljiosf af/d] f ;}4flGts cfwf/df ljleGg kl/sNkgf u/]sf 5g\ . h;cGtu{t
a|Xdf08sf] k;| f/ /f]lsP/ vD' rg ;'? x'g] 5 . o; jm| ddf ;Dk0" f{ kbfy{ Ps laGbd' f vl' DFrbf lau
jm| Gr -Big Crunch_ l;h{gf eO{ kg' M csf{] lau Aofª -Big Bang_ ;'? x'g] 5 .

a|Xdf08;Fu ;DalGwt j}1flgs tYox¿ / kj" Lo{ bzg{ lar tfbDotf (Correlation between

scientific facts about the universe and eastern philosophy)

ljleGg wdfj{ nDaLx¿sf] bz{g

bzg{ j}1flgs lrGtgx¿sf] oyfy{tf xf] . of] zf:jt jf:tljstfsf] l;4fGt xf] . bzg{ zf:qn]
hLjg k4ltnfO{ lgb{l] zt ub{5 . dflg;sf lh1f;f jf st' x' ntf k/" f ug{] ;Gbed{ f g} bzg{ sf]
pTklQ ePsf] xf] . dflg;n] jftfj/0f s] xf] < jftfj/0f lsg kl/jtg{ zLn 5 < kl/jt{gzLn
x'gfsf sf/0fx¿ s] s] xg' \ < hLjg s] xf] < cfTdf s] xf] < dT[ o' s] xf] < :ju{ s] xf] < gs{ s] xf]
< h:tf ljljw kIfsf af/d] f hfGg,] ;'Gg], xg] {], ae' mg\ ,] sf/0f kQf nufpg] k|of;af6 g} bz{gsf]
pTklQ ePsf] xf] . s,] lsg, s;/L slxn] h:tf k|Zgx¿sf] pQ/ vf]Hg] jm| dsf] lh1f;fn] bz{gsf]
pTklQ ePsf] dflgG5 .

j}lbs bzg{ nfO{ lxGb' bzg{ , cfo{ bzg{ / ;gftg bz{g eg]/ klg lrlgG5 . j]bdf cfwfl/t bzg{
ePsfn] of] jl} bs bzg{ xf] . kj" {]nL bz{gsf] pTklQsf] cfwf/ j]b xf] . jb] rf/cf]6f 5g\ CUjb] ,
;fdj]b, oh'jb{] / cy{j{jb] . oL rf/ jb] sf] lgisif{ pklgifb\ u|Gy xf] . pklgifba\ f6} !* k/' f0f
ags] f x'g\ . ;a} jb] , pklgifb\ k'/f0fsf] lgisif{ uLtf xf] .

j}lbs bzg{ cg;' f/ aXdf08sf] cfo'

j}lbs bzg{ cg;' f/ aXdf08sf] cfo' rf/ ou' df ljeflht 5 . o;nfO{ jm| dzM ;To o'u, qt] f
o'u, åjfk/ o'u / snL o'udf juLs{ /0f ul/Psf] 5 . of] cjlw 4.32 ldlnog dfgj jif{ xG' 5 .
Ps xhf/ o:tf r/0f k/" f x'bF f ax| d\ f08sf] Ps lbg x'G5 . t;y{ a|Xdfsf] Ps lbg 4.32 ldlnog
× 1000 Ö 4.32 ca{ dfgj jifs{ f] xG' 5 . k|Tos] ax| \dfsf] lbgnfO{ æsNkæ elgG5 . a|Xdfsf] /ft
klg 4.32 c/a dfgj jif{sf] x'G5 . aX| dfsf] lbgsf] ;dodf aX| df08df hLjx¿ hLljt /xG5g\

lj1fg tyf kl| jlwM sIff ( 199

/ /ftsf] ;dodf s'g} hLjx¿ /xbF g} g\ . t;y{ a|Xdfsf] Ps lbg / Ps /ftdf hDdf 8.64 ca{
dfgj jifx{ ¿ 5g\ .

aX| dfsf] pd]/ !)) jif{ xf] . aX| dfsf] kT| os] jif{ 360 lbg / 360 /ft xG' 5g\ . o;n} ] a|Xdfsf] sn'
pd/] 8.64 c/a × 100 × 360 Ö 311,040 c/a dfgj jif{ xf] . of] cjlwnfO{ dxfsNk elgG5
. aX| df08sf] cfo' Ps dxfsNk xf] .

a4' bzg{ uft} d a4' af6 kl| tkflbt a'4 wd{af6 ljsf; ePsf] xf] . of] a'4 wd{df cfwfl/t bz{g
ePsfn] g} o;nfO{ a4' bz{g elgG5 . af}4 wdn{ ] ;[li6stf{ jf OZ{ j/ jf a|Xdfsf] cl:tTjnfO{
:jLsf/ ub{g} .

o;cg';f/ Ps cd/ cfTdf / cnf}lss zlStsf] cl:tTj 5g} . of] kbfy,{ efjgf, wf/0ff,
dfgl;s cj:yf / rt] gfdf ljZjf; ub{5 . af}4 wdc{ g';f/ d[To' dgfj] 1} flgs hLjgsf] cGTo
xf] . O:nfdjfbsf cg';f/ ;;+ f/sf] Pp6} dfq OZ{ j/ cNnfx, / ;+;f/sf ;j} j:tx' ¿sf] lgdf{tf
/ dflns cNnfx x'g\ .

…dG' wd' Ú Ps bz{gzf:q xf] . h;n] hLjg / hutn\ fO{ ;d"lrt 9ªu\ n] a'emfp5F . /fO{, ofVvf,
lnDa', ;g' j' f/ cyft{ \ …ls/ftÚ ;db' fon] ;lbof}F cl3 vf]h / ljsf; u/s] f] 1fg / ;fG} bo{sf]
e08f/ xf] of] . o;df dfgj hLjgn] cflbd ou' bl] v cfw'lgs ;Eotf;Dd u/s] f] ofqfsf] j0f{g
5 . d'Gw'dn] ;f/f ax| \df08, cfsfz, kY[ jL, hn, hLj, kI+ fL, jg:klt / dfgj ;l[ i6af/] lj:tf/
df atfpF5 .

ljm| ofsnfk 12.2
>JobZ[ o ;fduL| sf dfWooaf6 jf cGo ;|f]taf6 vfh] L u/L lj1fgsf] ljsf;jm| d ;u“ }
a|xd\ f08 ;DaGwL ae' mfOdf cfPsf kl/jtg{ x¿af/] 5nkmn ug'x{ f];\ . lj1fgsf ljleGg
tYox¿ ks| flzt xg' 'k"j{ ;dfhdf ax| d\ f08;DaGwL s] s:tf 1fgx¿ :yflkt 5g,\ vfh] L
ug{'xf];\ / ltgsf] lj1fg;u“ sf] lgs6tfsf af/d] f ;fyLx¿lar 5nkmn ugx'{ f;] \ M

a|Xdf08;DaGwL j}1flgs tYox¿ j1} flgs l;4fGt k"j{ ;dfhdf :yflkt wf/0ff

a|x\df08sf] pTklQ / o;sf] cfo'=======
===========================

===================

kj" Lo{ ;Eotfcg';f/ dflg;df ax| d\ f08sf vuf]nLo lk08x¿, vufn] Lo 36gfx¿, tf/fd08n,
u|xx¿ cflbsf af/]df k|frLg sfnb]lv hfgsf/L /x]sf] kfOG5 . Hofl] tif lj1fgcGtut{ ul/g]
vufn] Lo lk08x¿sf] cWoog Ps Jojl:yt cWoog xf] . j}1flgs l;4fGt kl| tkfbg x'g'kj" {sf]
;dob]lv ;dfhdf :yflkt sx] L wf/0ffx¿ / j}1flgs vf]hlar lgs6tf kfOG5\ .

200 lj1fg tyf k|ljlwM sIff (

lrq 12.5 kY[ jLsf] sIfLo rfn;u“ } ;o" { Pskl5 csf{] u/L 12 cf]6f /flzd08x¿df k|jz] ug{] jm| d

k[YjL ;o" {sf] jl/kl/ Ps sIfLo w/ftn -orbital plane_ df 3l' d/xs] f] x'G5 . jife{ l/ kY[ jL

cfk\mgf] ultn] sIfdf :yfg kl/jtg{ ub}{ Ps rSs/ k"/f u5{ . lrq 12.5 df b]vfOP h:t}
kY[ jLn] Ps jifd{ f ;"os{ f] kl/j|mdf ul//x]sf] cj:yfdf k[YjLaf6 x]bf{ ;"o{ klg k[YjLsf] sIfLo

w/ftn;uF } aflx/L cGtl/Ifdf xg' ] 12 cf6] f tf/fd08n -/flzd08n_ sf] ;fk]If ;/]sf] b]lvG5 .
o;/L kY[ jLaf6 xb] f{ jif{el/df ;"on{ ] jm| dzM ;a} /flzdf k|j]z u/s] f] bl] vG5 .

kj" Lo{ bzg{ cg;' f/ ;"o{n] /flz kl/jt{g lrq 12.6 rGb|dfsf] sIf / k[YjLaf6 x]bf{ rGbd| f
ugn{' fO{ ;ª\jm| flGt -solstice_ dflgG5 . ;o" { wg' ;u“ } aflx/L cGtl/Ifdf b]lvg] tf/fd08n
/flzaf6 ds/df k|j]z ubf{ ds/ ;ªj\ |mflGt
-winter solstice_ / ;"o{ ldy'g /flzaf6 ss6{
/flzdf k|j]z ubf{ ss{6 ;ª\j|mflGt -cancer
solstice or summer solstice_ dflgG5 .
;fo} { jif{sf] ;?' cft ds/ ;ªj\ |mflGtaf6
xG' 5 . ds/ ;ª\j|mflGt b]lv ss{6 ;ªj\ |mflGt;Ddsf]
6 dlxgf;Ddsf] cjlwnfO{ pQ/fo0f / To;kl5
ss{6 ;ªj\ |mflGtaf6 k'gM ds/ ;ª\j|mflGt;Ddsf]
6 dlxgfsf] ;donfO{ blIf0ffog dflgG5 . Ps
ds/ ;ªj\ |mflGtaf6 csf]{ ds/ ;ªj\ m| flGt;Ddsf]
cjlwnfO} ;fo} { jif{ -solar year_ elgG5 .
;fo} { jif{ / rGb| jifl{ arsf] ;dofGt/ ldnfpbF f
k|Tos] tLg jif{df dndf; kg{] u5{ .

;o" { jm| dzM 12 /flzd08n -di] f /flzaf6 dLg /flz_ df ed| 0f u/] h:t} rGbd| fn] jm| dzM 27 cf]6f
gIfqx¿df ed| 0f ug]{ dfGotf 5 . o; cjlwnfO{ gIfqdf; elgG5 . of] ;do 27 lbgsf] x'G5 .
o; cjlwdf kY[ jLaf6 xb] f{ rGbd| fn] nueu 2.25 lbgsf] cGt/fndf Ps /flz d08naf6 csf{]
/flz d08ndf kj| ]z u/s] f] bl] vG5 . kj" Lo{ bz{gcg;' f/ gofF hGds] f] aRrfsf] hGd ;docg';f/
cIfdf xg' ] rGb|dfsf] :yfg / aflx/L cGtl/Ifdf bl] vg] rGb|df ;Fus} f] /flz d08nsf cfwf/df
/flz lrx\g 56' \ofOG5 .

lj1fg tyf kl| jlwM sIff ( 201

;dfhdf ax| d\ f08sf af/]df j}1flgs tYox¿sf] 1fg xg' ' k"j{ g} a|x\df08sf] ;l[ i6, u|x, tf/fd08n,
ljleGg vufn] Lo 36gfx¿af/] cfk\mg} lsl;dsf] a'emfO /xs] f] lyof] . pbfx/0fsf ¿kdf u|x0f
sj] n cf;}F L jf kl" 0f{dfsf lbg nfUg] u5{ . o; cj:yfdf ;"os{ f] pHofnf] 5]lsga] f/] dflg;x¿df
cfkm\ g} lsl;dsf] a'emfO lyof] . Hof]ltif zf:qcg';f/ ;o" {, kY[ jL, / rGbd| fsf] ;DalGwt sIfdf
x'g] :yfgaf/] u0fgf u/L SofnG] 8/df ux| 0f nfUg] lbg pNnv] ul/Psf] x'G5 . jl} bs bz{gcg;' f/
gj ux| x¿sf] cjwf/0ff cflb sfnb]lv /xL cfPsf] lyof] . logLx¿ cfk\mgf] sIf eP/ cufl8
a9\g] wf/0f ljBdfg lyof] . k"jLo{ bz{gcg;' f/ sg' } tf/fd08ndf cjl:yt tf/fx¿ cfcfkm\ gf]
:yfgdf /xg] tyf Ct'cg';f/ cfsfzdf km/s km/s :yfgdf bl] vga] f/] hfgsf/L lyof] . ;KtClif

-ursa major_, n3' ;KtClif -ursa minor_, wj|' t| f/f cflbsf] :yfgaf/] kf/} fl0fs syfx¿df
pNn]v ul/Psf] kfOG5 .

zlSt ;l~rtsf] l;4fGt (Principle of conservation of energy)

lj|mofsnfk 12.3

a|x\df08df ePsf s]xL ;hLj tyf lghL{jx¿sf] lglZrt cfok' Zrft\ xg' ] zlStsf] ¿kfGt/0faf/]
5nkmn ugx{ f];\ M

;hLj÷lghLj{ cfo' d[To' ÷gfz x'b“ f xg' ] kbfy{ / zlStsf] ¿kfGt/0f
tf/fsf] hLjgL gfz ePkl5 k'gM a|Xdf08d} ldl;g]
dflg; ===========
sf7
tf/f

kY[ jLdf /x]sf kbfy{x¿ aX| df08sf] l;hg{ fsf an] f 5l/Psf kbfy{x¿ g} xg' \ . a|Xdf08df h]
hlt kbfy{ tyf pmhf{ /xs] f] 5 Tof] aX| df08 l;hg{ fsf an] fbl] v /lxcfPsf] xf] . zlSt g pTkGg
ug{ ;lsG5 g t gi6 g} ug{ ;lsG5, of] Ps ¿kaf6 csf{d] f ¿kfGt/0f xG' 5 . kY[ jLdf xg' ]
hLjx¿sf] hLjgrjm| , hn rj|m, /f;folgs rjm| nufot cGtl/Ifdf x'g] tf/fx¿sf] hLjgrj|maf6
k|f0fLnufot aX| df08sf ;a} j:tx' ¿sf] lglZrt cfo' xG' 5 eGg] lgisif{ lgsfNg ;lsG5 . cfo'
;dfKt eO;s]kl5 k'gM zlSt / kbfy{ aX| df08d} ;dflxt xG' 5g\ . k"jLo{ dfGotfcg;' f/ dfgj
z/L/ h8 tŒj xf] . o;nfO{ cfTdf¿kL zlStn] ;~rfng ul//x]sf] xG' 5 . d[To'sf jm| ddf cfTdf
5'6l\ 6P/ a|Xdf08df hfG5 . pSt tŒj slxNo} gf; xbF' g} . kj" L{o bz{gcg;' f/ d[To' ;:+ sf/sf
j|mddf ul/g] ljm| ofsnfkaf6 z/L/sf k~r tŒjx¿ kY[ jL, hn, jfo', clUg / cGtl/If a|Xdf08d}
;dflxt xg' ] ljZjf; /x]sf] kfOG5 .

kl/of]hgf sfo{

xfd|f] ;dfhdf cGtl/If lj1fgsf] eGbf Hof]ltif lj1fgsf] ke| fj a9L /xs] f] kfOG5 eGg] zLifs{ df
ljleGg ;Gbe{ ;fdu|Lx¿df vf]hL u/L lgaGw n]Vgx' f];\ / sIffdf 5nkmn ug{'xf];\ .

202 lj1fg tyf k|ljlwM sIff (

cEof;

!= ;xL pQ/ 5fGgx' f;] \ M
s_ ga] n' fdf x'g] kd| 'v tŒj s'g xf] <
-c_ lxlnod -cf_ sfag{
-O_ gfO6f« h] g -O_{ xfO8«f]hg
-v_ tf/fsf] d[Tos' f j|mddf x'g] Ps 7n' f] lj:kmf6] g ===================== xf] .
-c_ kN;/ -cf_ Go'6f« g] tf/f
-O_ ;k' / gfe] f -O_{ ANofs xf]n
-u_ tf/fsf] hLjgrj|msf nflu s'g ;xL j|md xf] <
-c_ ga] 'nf → kf| ]6f]:6f/ → tf/f → /]8 hfOG6 → ;k' / gf]ef → ANofs 8km{
-cf_ ga] 'nf → k|f6] f]:6f/ → tf/f → ;k/gf]ef → /]8 hfOG6 → ANofs xfn]
-O_ ga] n' f → kf| 6] f:] 6f/ → tf/f → /8] ;k' / hfOG6 → ;k' / gfe] f → ANofs xfn]
-O_{ ga] n' f → kf| 6] f:] 6f/ → tf/f → /8] ;k' / hfOG6 → ;k' / gfe] f → AxfO6 8km{
-3_ lbOPsf dWo] sg' aX| df08;Fu ;DalGwt tYo xf] <
-c_ aX| df08 Ps lglZrt ;Ldf;Dd km} lnPsf] 5 .
-cf_ aX| df08sf ;a} kbfy{ tyf pmhf{sf] pTklQ Ps ;femf lk08af6 ePsf] xf] .
-O_ a|Xdf08df cjl:yt zlSt kl/jtg{ eO/G5 .
-O_{ aX| df08df cjl:yt kbfy{ gfz xbF' f zlSt 365\ .
@= km/s nV] gx' f];\ M
-s_ kf| 6] f] :6f/ -protostar_ / tf/f -star_
-v_ /8] hfOG6 / /]8 ;'k/ hfOG6
-u_ gfe] f / ;k' / gf]ef

lj1fg tyf kl| jlwM sIff ( 203

#= sf/0f nV] gx' f;] \ M

-s_ g]an' fnfO{ :6]n/ g;/{ L -staller nursery_ klg elgG5 .
-v_ tf/fx¿ ;a} Ps} /ªsf xFb' }gg\ .
-u_ ANofs xf]nnfO{ b]Vg ;lsbF }g .

-3_ ;f}od{ 08ndf /xs] f Uof;F hfOG6 -gas giant_ a[x:kltnfO{ c;kmn tf/f -failed star_
klg elgG5 .

$= tnsf k|Zgx¿sf] pQ/ n]Vgx' f;] \ M
-s_ g]a'nf egs] f] s] xf] <
-v_ ANofs xfn] egs] f] s] xf] <
-u_ tf/fsf] hLjgrj|msf] lrq;lxt JofVof ugx{' f;] \ .
-3_ sfnfGt/df ;"os{ f] OGwg ;dflKtkl5 o;sf] cj:yf s:tf] xfn] f, JofVof ug'{xf];\ .
-ª_ aX| df08;DaGwL s]xL j1} flgs tYox¿ n]Vgx' f];\ .
-r_ ax| df08;DaGwL j1} flgs tYox¿ / k"jLo{ bz{glar tfbDotf JofVof ugx{' f];\ .
-5_ a|Xdf08;DaGwL j}1flgs tYox¿ k|sflzt xg' ' k"j{ a|Xdf08;DaGwL k"jL{o ;Eotfdf
/x]sf] 1fgsf af/]df Ps lgaGw n]Vg'xf;] \ .

-h_ zlSt ;l~rtsf] l;4fGt -principle of conservation of energy_ cfwf/df aX| df08df
ePsf] zlSt / kbfy{ aX| df08d} ;dflxt xG' 5 eGg] tYo pbfx/0f;lxt kl' i6
ug'x{ f;] \ .

204 lj1fg tyf kl| jlwM sIff (

!# ;"rgf tyf ;~rf/ k|ljlw
(Information and Communication Technology)

hfh/sf]6sf bu' d{ tLg ufpk“ flnsfdf gk] fnL e"pkux| -gk] fnL :of6–!_ kI| f]k0f,
6]lnsdsf] ;~rf/ ;l' jwf lj:tf/ g]kfn cGtl/If ou' df k|j]z

lrq 13.1 b/" ;~rf/sf] ;ªs\ t] l/l;e/ / 6f« G;ld6/ lrq 13.2 cd]l/sfsf] elhl{ gofaf6 kI| fk] 0f
ul/Psf] g]kfnsf] klxnf] e"pku|x
w'|j| xfQLdf ;]6n] fO6 /]l8of] sn/
-satellite radio collar_ /flvof] OG6/g6] n] k]m/]sf] l6eLsf] dx' f/

lrq 13.3 xfQLsf] 3f“6Ldf /l] 8of] sn/ nufOb} lrq 13.4 g]kfn 6l] nlehgsf] 6/] ]l:6o« n,
:of6]nfO6 / OG6/g6] tLgcf6] } dfWodaf6 k|;f/0f

lj|mofsnfk 13.1

dflysf ;dfrf/ zLif{sx¿ ljleGg kqklqsf tyf cgnfOg ;dfrf/ kf]6{n -News portal_
af6 lnOPsf x'g\ . oL ;dfrf/x¿ ;~rf/ k|ljlw;u“ ;DalGwt 5g\ . OG6/g6] hl8t
sDKo6' /df af| ph/ -browser- e.g. chrome_ vfN] gx' f;] \ / ;r{ OlGhg -search engine: e.g.
www.google.com_ df oL ;dfrf/sf zLifs{ 6fOk u/L k"0f{ ;dfrf/sf] vfh] L ugx'{ f;] \ .
;dfrf/ k9/] k|fKt hfgsf/Lsf cfwf/df ;DalGwt k|ljlwsf lsl;d, k|ofu] sf] sf/0f,
kmfObf cflbsf af/d] f 5nkmn ug{'xf];\ .

lj1fg tyf k|ljlwM sIff ( 205

xfdL ;"rgf tyf ;~rf/ k|ljlw -ICT_ sf] ou' df 5fF} . ICT sf] tLj| ljsf;jm| d;Fu} ko| f]udf
cfPsf 6]lnkmfg] , df]afOn kmfg] , ˆofS; dl] ;g, sDKo'6/ / OG6/g6] n] ljZjsf ljleGg :yfgx¿nfO{
;~rf/sf dfWodaf6 hf]8s] f] 5 . ;~rf/sf nflu k|ofu] x'g] cfjfh, zAb, lrq, lel8of], cflbnfO{
sDKo6' /df 8f6fsf ¿kdf e08f/0f u/L ltgnfO{ OG6/g]6dfkm{ t 6f9f 6f9fsf :yfgx¿df ;fg{
/ ko| fu] ug{ ;Dej ePsf] 5 . ICT Ps ljBt' Lo pks/0fsf] dbtn] 7'nf] dfqfdf ;"rgfx¿
e08f/0f ug],{ k|zfw] g ug]{ / k;| f/0f ug{] dfWod xf] . ;~rf/ ep" ku|x -communication satellite_
sf] k|ofu] n] ICT sf] ljsf;nfO{ cem} cTofw'lgs agfPsf] 5 .

s[lqd e"pkux| / o;sf] k|of]u (Artificial satellite and its application)

ep" ku|xx¿nfO{ k[YjLsf] jl/kl/ ljleGg sIf;Dd k¥' ofpg]
ljlw, ltgnfO{ km/s km/s sIfdf /flvgs' f sf/0f, kY[ jL /
ep" kux| larsf] ;~rf/ cflbsf af/d] f 5nkmn ugx{' f;] \ .

k[YjLsf] jl/kl/ lglZrt sIfdf lg/Gt/ kl/jm| df ug]{ dfgj
lgld{t j:t'nfO{ ep" kux| elgG5 . s[lqd e"pku|xx¿ k[YjLsf]
kl/jm| df ug{] dfgj lgldt{ j:tx' ¿ xg' \ . ltgLx¿nfO{ /s]6df lrq 13.3 sl[ qd ep" kux| ¿sf sIf
/fvL lglZrt prfOdf k'¥ofOG5 / u'?Tjansf] lbzf;uF nDa
xg' ] u/L lglZrt ultdf kI| fk] 0f ul/G5 . To;kl5 o;n] ;f]xL prfOdf /x/]
kY[ jLnfO{ lg/Gt/ kl/jm| df ul//xG5 . sl[ qd ep" ku|xx¿ lg/Gt/ 3'ld/xg
yk phf{sf] cfjZostf kbg{} lsgls ToxfF jfod' 08nLo 3if0{ f xb'F }g . t/
o;leq /x]sf sDKo'6/ / cGo pks/0fx¿ ;~rfng ug{sf nflu eg] ;f}o{
pmhf{sf] ko| fu] ul/G5 .

klxnf] sl[ qd ep" ku|x :kt' lgs–1 (Sputanki-1) xf] . o;nfO{ ;f]leot ;ª\3n] ;g\ 1957
cS6f]a/ 4 tfl/ssf lbg kI| fk] 0f u/]sf] lyof] .

e"pkux| / kY[ jL l:yt u|fpG8 :6];g -ground station_ sf lrq 13.3 cklnª\s / 8fpglnª\s
lar t/ªu\ x¿ dfkm{ t ;DaGw :yflkt ul/Psf] xG' 5 . e"pku|xn]
k[YjLsf] uf| pG8 :6];gaf6 ;ª\st] k|fKt ub5{ h;nfO{ cklnª\s
;ª\s]t -uplink signal_ elgG5 . pSt ;ªs\ ]tnfO{ yk
zlStzfnL t/ªu\ df ¿kfGt/0f u/L k'gM kY[ jLtk{m kmsf{OlbG5
h;nfO{ 8fpglnª\s ;ªs\ ]t -downlink signal_ elgG5 .

sl[ qd ep" kux| sf sIfx¿

lgDg kY[ jL sIf dWod kY[ jL sIf e:" yfoL sIf -

(LEO) – (MEO) – (2,000 km- (GEO) –35,786 km)
(180 km-2,000 km) 35,786 km)
lj1fg tyf k|ljlwM sIff (
206

lj|mofsnfk 13.2

>JobZ[ o ;fduL| tyf rf6{sf dfWodaf6 s[lqd ep" kux| sf af/]df hfgsf/Lx¿ ;ªs\ ng ug{x' f;] \
/ tnsf] tflnsfdf eg{x' f];\ .

sIf -orbit_ ljz]iftf k|ofh] g pbfx/0f

lgDg k[YjL sIf -Low earth orbit-LEO_ ===================== ===================== =====================
===================== =====================
dWod k[YjL sIf -medium earth orbit- =====================
===================== =====================
MEO_

e":yfoL sIf -geostationary orbit-GEO_ =====================

e"pkux| x¿nfO{ ltgsf] p2]Zosf cfwf/df ljleGg sIfdf k|If]k0f ul/G5 . k[YjLsf] cjnf]sg
ug,{] ;txsf] tl:a/ lvRg], j}1flgs cg;' Gwfg ug{] h:tf sfo{sf nflu ep" kux| nfO{ lgDg k[YjL
sIfdf k|Ifk] 0f ul/G5 . of] sIf k[YjLsf] ;txsf] glhs xg' ] ePsfn] kl/jm| df ug{ nfUg] ;do
-orbital period_ lgs} 5f]6f] xG' 5 . h;n] ubf{ kY[ jLsf] sg' } :yfg dflysf] cfsfzdf ep" ku|x
5f6] f] ;dosf nflu dfq /xG5 / Ps} lbgdf klg kY[ jLsf w]/} efux¿sf] cjnfs] g ug{ ;lsG5 .
kY[ jLsf] ;txaf6 sl/a 408 km sf] prfOdf 3'ld/x]sf] cGt/f{li6«o cGtl/If s]Gb| -International
Space Station-ISS_ klg LEO e"pku|x xf] . o;n] nueu 90 ldg]6df k[YjLsf] Ps rSs/
k"/f u5{ . of] j}1flgs k|of]uzfnf xf] / j1} flgsx¿ dlxgf;F} Dd oxfF a;/] j1} flgs k|of]u tyf
cg;' Gwfg u5g{ \ .

dWod k[YjL sIfcGtu{t sl/a 20,200 km sf] prfOdf kI| fk] 0f lrq 13.7 MEO df
ep" kux| x¿sf] ;~hfn
ul/Psf g]leu];g e"pku|xx¿nfO{ kY[ jLsf] kl/jm| df ug{ nueu 12
306f nfU5 . kY[ jLsf] ;Dk0" f{ efu dfly e"pkux| x¿sf] kxrF k'¥ofpg
;+Fu}sf] lrq 13.7 df bv] fOP h:t} dWod kY[ jL sIfdf ;~hfn
xg' ] u/L 24 cf6] f g]leu;] g e"pkux| x¿ kI| f]k0f ul/G5 . gl] eu;] g
e"pkux| sf dbtn] k[YjLdf j:tx' ¿sf] :yfg kQf nufpg ;lsG5 .
o; k0| ffnLnfO{ lhlkP; -global positioning system-GPS_ elgG5 .

ed" Wo /]vLo efu dfly kg{] e":yfoL sIfdf /xs] f ep" kux| n] k[YjLsf]

kl/jm| df ug{ 23 306f 56 ldg6] 4 ;]sG] 8 ;do nfU5 . of] ;do

k[YjLn] cfkm\ gf] cIfdf Ps kmGsf k"/f ug{ nfUg] ;do -rotational

period_ ;F+u a/fa/ xG' 5 . h;n] ubf{ e"pku|x ;wF} k[YjLsf] ;tx;uF

;fk]lIfs ¿kdf l:y/ x'G5 . oL ep" kux| x¿n] 6l] nlehg, 6]lnkmfg] ,

dfa] fOn tyf OG6/g]6 ;ª\st] k|;f/0f u/L b'/;~rf/df ;xofu]

u5g{ \ . LEO / MEO ep" kux| x¿n] klg e"pkux| s} ;xfotfn] u|fpG8 lrq 13.8 e"pku|xsf ko| f]ux¿
:6;] g;Fu ;~rf/ cbfgkb| fg u5g{ \ . e":yfO{ sIfdf ljZjsf w]/}

b]zx¿n] ;~rf/ ep" kux| x¿ k|Ifk] 0f ul/;s]sf 5g\ .

lj1fg tyf k|ljlwM sIff ( 207

gk] fnL:of6 – 1 (NepaliSat-1)

ljm| ofsnfk 13.3

g]kfnsf] klxnf] e"pkux| sf af/d] f >JobZ[ o ;fdu|Lsf] cjnf]sg ug{'xf;] \ / o;af/]sf hfgsf/Lx¿
;ªs\ ng u/L sIffdf 5nkmn ug'x{ f];\ .

gk] fnL;6] –1 gk] fnsf] klxnf] ep" ku|x xf] . o;sf] lgdf{0f g]kfn

lj1fg tyf k|ljlw k1| f k|lti7fg -NAST_ sf] cflys{ ;xof]udf

hfkfgsf] So'6s] ljZjljBfno -Kyutech University_ af6

:k;] 6]Sgfn] fh] Ldf Ol~hlgol/ª ul//xs] f cfefif df:s]

/ Onl] S6s« n OlGhlgol/ªdf :gftsf]Q/ ul//x]sf xl//fd

>]i7n] u/s] f lyP . of] 3gfsf/ ;I" d e"pku|x -cubical

nanosatellite_ sf] lk08 1.33 kg 5 . o;nfO{ ;+o'St /fHo

cd]l/sfsf] elh{lgofaf6 ;g\ 2019 clkn| 18 sf lbg k|If]k0f

ul/Psf] lyof] . To;sf] Ps dlxgfkl5 cGt/fl{ i6«o cGtl/If lrq 13.8 gk] fnL ;6] – 1
sG] b| -ISS_ af6 ;g\ 2019 h'g 17 sf lbg o;nfO{ kY[ jLsf]

;txaf6 sl/a 400 km sf] prfOsf] sIfdf 5f]l8Psf] lyof] . o;n] sl/a 90 ldg]6df kY[ jLsf]

Ps rSs/ k"/f u5{ . of] 6 b]lv 10 ldg]6 g]kfnsf] cfsfzdfly /xG5 . o;nfO{ g]kfnsf] e"jgf6] ,

jghªu\ n, lxdgbL, kxf8, ;8s, cflbsf tl:a/x¿ lvr]/ k;| f/0f ug{] sfos{ f nflu k|Ifk] 0f

ul/Psf] xf] .

;"rgf tyf ;~rf/ k|ljlwsf] ko| fu] (Use of information and communication technology)

ljm| ofsnfk 13.4

tkfOn“{ ] b}lgs hLjgdf kqklqsf, /l] 8of,] 6]lnlehg, 6]lnkmf]g, k\mofS;, df]afOn kmfg] ,
jfOkmfO, Odn] , OG6/g]6, lhlkP; cflbsf] ko| fu] s'g sg' ko| fh] gsf nflu ug{'xG' 5 <
logLx¿sf] ko| f]uaf/] sIffdf 5nkmn ug{x' f];\ / ;d"xdf sfo{ u/L kh|] G6;] g jf kf:] 6/ tof/
kfgx'{ f;] \ . cfk"mn] tof/ kf/s] f ;fduL| nfO{ sIffdf k|:tt' ug{x' f;] \ .

kqklqsf, /l] 8of,] 6l] nlehg (Magazine, Radio and lrq 13.10.
lj1fg tyf kl| jlwM sIff (
Television)

kqklqsfx¿n] cfk\mgf] jl/kl/ tyf ljZjsf ljleGg 7fpFsf
hfgsf/L / ;fdfGo 1fg kb| fg ub5{ g\ . logdf cflys{ ultljlw,
/fhgLlts 36gf, vn] s'b ljm| ofsnfk, dgf/] ~hgnufot
1fgjws{ ;dfrf/ tyf n]vx¿ k|sf;g ul/Psf xG' 5g\ . tLdWo]
cfkm\ gf] ?lrsf ljifoj:t' k9/] hfgsf/L tyf 1fg xfl;n ug{
;lsG5 . ;"rgf k|;f/0fdf kqklqsfsf] eGbf ax[ t\ kx'Fr /]l8ofs] f]
xG' 5 . /]l8of] ;ª\s]t cfsfzdf ljBt' \ r'DasLo t/ªu\ dfkm{ t\

208

k;| f/0f xg' ] ePsfn] /l] 8ofa] f6 ;r" gf, hfgsf/L, ;dfrf/, 1fgaws{ ljifj:tx' ¿, dfgf/] ~hg;DaGwL
uLt;ªu\ Lt, syf sljtf cflb k;| f/0f u/L Psbd} l56f] >ft] f;dIf k¥' ofpg ;lsG5 .

O6nLsf ul' UnPndf] dfsf]{gL -Guglielmo Marconi_ n] ;jk{ y| d /l] 8of] ;ª\st] -radio
signal_ nfO{ nfdf] b/' Ldf k7fpg ;lsG5 eg]/ kd| fl0ft u/]sf lyP .

6l] nlehgsf dfWoodaf6 xfdLn] bl} gs b]z tyf lrq 13.11
ljZjsf 36gf, df;} d;DaGwL hfgsf/L, lzIff, vf]h,
lj1fg, ks| l[ t, dgf/] ~hg cflb ;DaGwL sfoj{ m| dsf]
cjnf]sg ug{ ;lsG5 . 6l] nlehgsf dfWodaf6
ljZjsf ljleGg 7fpFdf v]lng] vn] s'bsf] k|ToIf
k;| f/0f x]g{ ;lsG5 . ljZjsf ljleGg b]zx¿af6
k|;fl/t sfoj{ m| dx¿ t/ªu\ ÷tf/sf dfWodaf6
xfdf| ] 3/sf] 6l] nlehg;Dd cfOk'U5g\ .

6]lnkmfg] , k\mofS;, df]afOn kmf]g (Telephone, Fax and mobile phone)

6l] nkmf]gsf dfWodaf6 b'O{ km/s :yfgdf

/xs] f JolStx¿lar s/' fsfgL ug{ ;lsG5 . Pp6f

6]lnkmf]gaf6 afn] ]sf] cfjfh o;sf] dfOjm| f]kmfg] n]

/s] 8{ u5{ / Onl] S6«sn ;ªs\ t] -electrical signal_

df ¿kfGt/0f x'G5 . pSt ;ª\s]t tf/af6 k;| fl/t

ul/G5 / csf{] 6]lnkmf]gaf6 ;ª\st] ¿kfGt/0f

eP/ k'gM cfjfhsf ¿kdf ;'Gg ;lsG5 . 6l] nkmf]g

nfOgdfkm{ t ˆofS; ug{ ;lsG5 . o;dfkm{ t lrq

/ cIf/sf ¿kdf k|:tt' ul/Psf ;r" gfnfO{ Ps lrq 13.12
:yfgaf6 csf]{df k|;fl/t ul/G5 . ˆofS; ubf{

6«fG;ld6 dl] ;g -transmit machine_ n] :Sofg/ -scanner_ sf] ko| f]u u/]/ lrq jf cIf/x¿nfO{

ljB'tLo ;ª\st] df ¿kfGt/0f ub{5 . pSt ;ª\st] nfO{ 6]lnkmf]g nfOgsf dfWodaf6 k7fpg

vf]h]sf] :yfgsf] d]l;gdf k;| f/0f ul/G5 . ˆofS; kf| Kt ug{] dl] ;gn] k|;f/0f ul/Psf] ;ª\s]tnfO{

jf:tljs lrq jf cIf/df abN5 / lkG| 6 ub5{ . df]afOn kmfg] sf] cflj:sf/ eP;Fu} s/' fsgL ug{

/ ;Gb]z 6fOk u//] k7fpg ;xh eof] . df]afOn kmf]g cfjfhnfO{ cl8of] ;ª\st] df ¿kfGt/0f

u//] t/ª\usf dfWoodaf6 k|;f/0f ug{ / o;sf] l7s ljk/Lt t/ª\usf ¿kdf cfPsf ;ª\s]tnfO{

kg' M cfjfhdf ¿kfGt/0f ug{ ;Sg] pks/0f xf] .

ˆofS;sf] cfljisf/ :s6NofG8sf cn]SHofG8/ ag} -Alexander Bain_ n] ;g\ 1842 df u/s] f
lyP . ;g\ 1924 df ˆofS;sf] k|ofu] af6 klxnf] k6s lSnen]G8 -Cleveland_ af6 Go'ofs] { -New
York_ df kmf]6f] k7fOPsf] lyof] .

lj1fg tyf kl| jlwM sIff ( 209

cgnfOg ;'ljwfx¿

g]leu];g cg';Gwfg
OG6/g]6 l6eL
;~rf/

lzIff -O–nlgª{ _ j]ljgf/÷uf]li7

:jf:Yo a}+lsª\ ;'ljwfx¿ lsgdn]

lrq 13.11 OG6/g6] ;'ljwfx¿

OG6/g]6, jfOkmfO, Od]n (Internet, Wifi and Email)

OG6/g6] ;+;f/sf] ;a}eGbf 7n' f] sDKo6' / g]6js{ -network_

xf] . df]afOn 8f6f, jfOkmfO, OG6/g6] k|bfos ;:+ yfn] lbPsf]

tf/ jf 6l] nkmfg] nfOgx¿dfkmt{ sDKo6' /x¿nfO{ g6] js{df

hf]8g\ ;lsG5 . plrt OG6/g]6 6n' sf] ko| fu] u//] xfdLx¿n]

OG6/g6] ;Fu+ hf]l8Psf ljleGg sDKo6' /x¿;uF ;Dks{ ug{ tyf
8f6fa];df e08f/ ul/Psf hfgsf/Lx¿ k|fKt ug{ ;S5f}F . lrq 13.15 df]afOn a+l} sªdfkm{ t
QR sf8]
pbfx/0fsf nflu u'un -google_, ofx' -yahoo_, ljª -bing_

h:tf ;r{ OlGhg -search engine_ sf] ko| fu] af6 cfkm\ gf] cWoogsf] ljifoaf/] hfgsf/Lx¿ vf]Hg

;lsG5 . ;~rf/, l;sfO ;fdu|Lx¿sf] vf]hL, dgf]/~hg, cgnfOg ;l' jwfx¿sf] k|ofu] cflb

OG6/g6] sf s]xL pkof]lutfx¿ xg' \ .

ljm| ofsnfk 13.5

sIffdf bO' {cf]6f :df6{ kmf]gdf ePsf] 8f6f÷kmfOn ;fg{] PlKns];g h:tM} ;o] / O6 -share
it_ n] jfOkmfO -Wi-Fi_ sf] ko| fu] af6 sg' } kmfOnnfO{ Pp6f kmfg] af6 csf]{ kmf]gdf ;f/s] f]
cjnfs] g ug'{xf;] \ .

jfOkmfO …jfO/n;] lkm8]n6] LÚ -Wireless fidelity_ sf] 5f6] f] lrq 13.16 jfOkmfO pks/0fx?
¿k xf] . of] tf//lxt g6] jlsª{ -wireless networking_
k|0ffnL xf] . jfOkmfOdf /]l8of] t/ª\u -radio wave_ sf
dfWoodaf6 pks/0fx¿lar ;Dks{ :yflkt ePsf] x'G5 .
o;sf] k|ofu] n] jfOkmfO ;'ljwf ePsf pks/0fx¿lar
8f6f -kmfOn_ ;fg{ tyf ltgnfO{ OG6/g]6;Fu h8fg ug{
;lsG5 . Nofk6k, :df6{ kmf]g, :df6{ 6l] nlehg, /fp6/
-router_ cflb pks/0fx¿df jfOkmfO ;l' jwf /flvPsf]

210 lj1fg tyf k|ljlwM sIff (

x'G5 . OG6/g]6sf] ko| fu] af6 Od]n k7fpg ;lsG5 . Odn] k7fpbF f Psl5gd} uGtJodf kU' g]
ePsfn] of] cfwl' gs ;~rf/sf] e/kbf]{ dfWod xf] . Odn] ;uF } sDKo6' / kmfOnx¿ klg k7fOG5 .
lhlkP; k|ljlw (Global Positioning System-GPS technology)

ljm| ofsnfk 13.5

Pp6f :df6{ kmfg] df OG6/g]6 ;]jf ;r' f? ug{x' f;] \ . cfk\mgf]
:df6{kmfg] sf] l:j|mgsf] dflyNnf] efuaf6 tnlt/ :jfOk
-swipe_ u/]/ lhlkP; nfs] ];g cg ug{'xf];\ . df]afOndf
ePsf] Dofk PlKns];gdf uP/ cfk\mgf] dfa] fOnsf] :yfg
cjnf]sg ug'{xf;] \ .

lhlkP; -GPS_ g]leu];g sg' } lhlkP; ;l' jwfoS' t pks/0fn] lhlkP;sf b'O{eGbf a9L
e"pku|xx¿af6 k|fKt t/ª\udfkm{ t b/' L lx;fa ug{] / pSt pks/0fsf] :yfg kQf nufpg]
k|ljlw xf] . lhlkP; -GPS_ Ps ;+o'St /fHo cd]l/sf -USA_ sf] :jfldTjdf /x]sf] e"pkux| df
cfwfl/t /l] 8of] gl] eu;] g k0| ffnL xf] . of] ;+oS' t /fHo cGtl/If an -United States Space
Force_ åf/f ;~rflnt 5 . ljZjsf ljleGg bz] x¿n] cfk\mg} gl] eu;] g k|0ffnL kI| fk] 0f u/s] f
5g\ . Russian Global Navigation Satellite System (GLONASS), European Union

Galileo positioning system, Chinese Compass navigation system, Indian Regional

Navigational Satellite System cflb ljZjsf ljleGg b]zx¿n] k|If]k0f u/s] f gl] eu;] g
k0| ffnLsf pbfx/0fx¿ x'g\ .

lrq 11.17 lrq 11.18 GPS 6«flsª lrq 11.19 GPS sf/ gl] eu;] g

;?' df lhlkP;sf] k|ofu] ;G} o ljm| ofsnfksf nflu ul/P klg xfn o;sf] ko| f]u w]/} Ifq] x¿df
ul/G5 . pbfx/0fsf nflu ;jf/L ;fwg 6«oflsª -tracking_, dflg; lxF8]sf] af6f] 6o« flsª ug],{
af6f] tyf :yfg kQf nufpg,] p8fg lgoGq0f ug]{, kz'kI+ fLx¿nfO{ 6«oflsª ug,]{ 6S] 6f]lgs

Kn6] rfn -tectonic plate movement_ sf] cWoog ug,{] kY[ jLsf] ;txsf] ;j]{If0f ug{] cflb
lhlkP;sf k|ofu] x¿ xg' \ .

lj1fg tyf k|ljlwM sIff ( 211

b/" ;~rf/ (Telecommunication)

b"/;~rf/ ljleGg lsl;dsf kl| jlwx¿sf] k|of]u u//] ;~rf/sf] ;ªs\ t] -communication
signal_ nfO{ tf/, clK6sn kmfOa/, t/ª\u cflbsf dfWoodaf6 Ps :yfgaf6 csf{] :yfgdf
k;| f/0f ug]{ k0| ffnL xf] . /]l8of] / 6]lnlehgaf6 ul/g] k;| f/0f, 6l] nkmfg] , km\ ofS;, df]afOn
kmfg] , OG6/g]6 cflbaf6 ul/g] ;~rf/ b/" ;~rf/sf pbfx/0fx¿ xg' \ . b/" ;~rf/df ljB'tLo /
ljBt' \ rD' asLo kl| jlwsf] k|of]u ul/G5 . 6]lnkmfg] df ;"rgfx¿nfO{ ljBt' Lo ;ª\st] -electrical
signal_ sf ¿kdf tf/dfkmt{ k7fOG5 . /l] 8of] ja] n] :yfgLo /]l8of] / 6]lnlehgaf6 k;| fl/t
;r" gfsf ;ªs\ ]tx¿ af]S5g\ . dfa] fOn kmfg] / /8f/ ;ªs\ ]t tyf cGtl/Ifdf /xs] f] ep" ku|x;uF sf]
;~rf/sf nflu dfOj|mf]ja] x¿ ko| f]u ul/G5g\ .

;g\ 1875 df cnS] HofG8/ uf| xd an] -Alexander Graham Bell_ n] cfjfhnfO{ ljBt' Lo
;ªs\ t] sf ¿kdf Ps 7fpa“ f6 csf]{ 7fpFdf k7fpg Ps ;/n 6]lnkmfg] df]8nsf] cflj:sf/
u/s] f lyP .

b"/;~rf/ k|ljlwsf] sfo{ l;4fGt (Working principle of telecommunication technology)

lj|mofsnfk 13.7

/]l8of÷] 6]lnlehg :6;] gsf] cjnfs] g ed| 0f jf >Job[Zo ;du|L, kf:] 6/ cflbsf dfWodaf6

b"/;~rf/ k|ljlwsf af/]df cWoog ugx'{ f;] \ . tn tflnsf pNn]v ul/Pem}F hfgsf/Lx¿
;ª\sng ug'x{ f];\ M

/s] l8{ª ljlw / ko| fu] xg' ] ;du|L, 6«fG;ld6/ k;| f/0f Rofgn l/l;e/
-PG6g] f, ;ªs\ t] se/h] _
-/l] 8of] ;ª\st] hg/] ]6/, ldS;/_, -t/ªu\ , cfj[lQ,
df]8o\ n' ];g, cflb 6fj/sf] prfO_ =======================

================================ ==============================

b/" ;~rf/ k|0ffnLdf ljleGg OnS] 6f« ]lgs tyf clK6sn pks/0fx¿dfkm{t ;r" gfx¿ Ps :yfgaf6
csfd{] f x:tfGt/0f ul/G5 . lrq 13.20 n] b/" ;~rf/ k0| ffnLsf tLg efusf ¿kdf 6f« G;ld6/,
k|;f/0f Rofgn, / l/l;e/nfO{ b]vfp5F .

Ogk6' k|;fl/t kf| Kt ;ª\st] cfp6k6' ;ªs\ t]

6f« G;ld6/ k|;f/0f Rofgn l/l;e/ ko| f]u stf{

lrq 13.20 b"/;~rf/ k0| ffnLsf d'Vo tLg cjojx¿

212 lj1fg tyf kl| jlwM sIff (

b/" ;~rf/ kl| jlwdf dfOj|mf]kmf]g, l6eL Sofd]/f jf sDKo6' /af6 kf| Kt x'g] ;r" gfx¿ Ogk6' x'g\ .
Ogk'6nfO{ 6f« G;ld6/n] ljBt' Lo pks/0fx¿sf] ko| fu] af6 kz| fw] g -processing_ u/L Ps 7fpaF f6
csf{] 7fpdF f k|;f/0fof]Uo ;~rf/sf] ;ªs\ ]t pTkGg ub5{ . o:tf] ;~rf/sf ;ªs\ t] n] sg' } cfjfh,
lrq, jf sDKo6' / 8f6f af]s]sf xg' ;S5g\ . pSt ;ª\st] nfO{ sg' } Rofgn -channel_ dfk{mt
k|;f/0f ul/G5 . ;~rf/sf] Rofgn /l] 8of] t/ª\ux¿ -radio waves_, dfOj|mf]j]a lad -microwave
beam_, wft' tf/ -metallic cable_, jf clK6sn kmfOa/ -optical fibre_ xg' ;S5 . cGTodf
pkoS' t pks/0fsf] ko| f]uaf6 k;| fl/t ;ª\s]tnfO{ k|fKt u/L rflxPsf] ¿kdf ¿kfGt/0f u/]/
ko| fu] ul/G5 .

df8] \o'n;] g / l8df8] o\ 'n];g (Modulation and demodulation)

ljm| ofsnfk 13.8

tkfO{“ /xs] f] :yfgdf /fl] 8ofd] fk{mt ;'Gg ;lsg] /l] 8of] t/ªx¿ sg' :yfgaf6 k;| f/0f
ul/G5g\ < tL t/ª\u k;| f/0f :6];gx¿sf af/]df hfgsf/Lx¿ vfh] L u/L tnsf] h:t} tflnsf
egx{' f];\ M

/l] 8of] t/ªu\ k|;f/0f t/ª\usf] cfjl[ Q df8] o\ 'n;] gsf lsl;d pStt/ªu\ ;'Gg;lsg]
ug]{ s]Gb| / o;sf] 7u] fgf :yfg÷lhNnfx¿
AM/FM
===================== ============ ==========================
==========================

6«fG;ld6/sf] PG6]gfaf6 pTkGg ;~rf/sf ;ªs\ t] l;w} ljBt' \ r'DasLo t/ª\udfkmt{ l/l;e/

PG6]gf -receiver antenna_ ;Dd hfG5g\ .

sltko ;ª\s]tx¿ jfod' 08nsf] cfofl] gs tx

-ionosphere_ df k'u/] ToxfaF f6 k/fjt{g eO{ sg' }

lglZrt b'/L;Dd 5l/G5g\ . xfdLn] ;G' g] :yfgLo

Pkm= Pd= -FM_ /]l8of] ;ª\s]t cfsfzLo t/ª\un]

af]s/] NofPsf] xG' 5 . nfdf] b'/Lsf k;| f/0fsf nflu

;~rf/sf ;ª\s]tnfO{ ljBt' \ rD' asLo t/ª\u

-cGtl/If t/ª\u_ sf ¿kdf ;~rf/ ep" ku|xdf
k7fOG5 / ToxfaF f6 kmsf{P/ kY[ jLsf] 7'nf] If]qdf lrq 13.21 t/ª\usf ¿kdf ;~rf/sf] ;ª\s]tsf]
k|;f/0f
k;| f/0f ul/G5 . ;~rf/ ep" kux| x¿n] ljZjJofkL

;~rf/ / kT| oIf k|;f/0fx¿ lgs} ;xh agfPsf] 5 .

/]l8of] t/ªu\ k;| f/0fsf nflu ;~rf/ ;"rgfsf] ks| [ltcg';f/ cfjl[ Q -frequency_ jf PDklnRo'8
-amplitude_ kl/jtg{ u/L k;| f/0f ul/G5 . o:tf] sfon{ fO{ df8] \o'n];g elgG5 . sd cfj[lQ ePsf
;"rgfsf ;ªs\ t] x¿ 7n' f] Ifq] df k;| f/0f xF'bg} g\ . o:tf ;ªs\ t] x¿nfO{ df]8o\ n' ;] gsf dffWodaf6
nfdf] b/' L;Dd k|;f/0f ug{ ;lsG5 . o;/L df]8o\ n' ];gdfkm{t k|;f/0f ul/Psf ;"rgfsf] ;ªs\ ]tnfO{
l8df]8\on' ];gdfkm{ t kg' M kf| Kt ul/G5 . l8df8] \on' ];g ljm| of ;ªs\ t] kf| Kt ug]{ pks/0fdf xG' 5 .

lj1fg tyf kl| jlwM sIff ( 213

lrq 13.22 /]l8of] 6«fG;ld6/ / /]l8of] lrq 13.23 l6eL t/ªu\ k;| f/0f lrq 13.24 OG6/g6] ;ª\st] k|;f/0f

cl8of] cfj[lQ -audio frequency_ /l] 8of] cjl[ Q -radio frequency_ eGbf lgs} sd x'G5 . t;y{
/l] 8of] t/ªu\ k|;f/0fsf nflu ;jk{ y| d Psgf;sf] cj[lQ ePsf] /l] 8of] ;ªs\ ]t -Radio signal_
pTkGg u/fOG5 . pSt ;ª\s]tnfO{ sl] /o/ -carrier_ elgG5 . /]l8ofd] fkm{ t ;~rf/sf] ;ª\s]tnfO{
k;| f/0f k"j{ cl8of] ;ªs\ ]t -audio signal_ cg;' f/ df]8o\ 'n]6 -modulate_ ul/G5 . cl8of] ;ª\s]t
/ lel8of] ;ªs\ ]tsf 8f6f k|s[lt km/s xg' ] ePsfn] nflu 56' \65'66\ } lsl;dn] df8] \on' ;] g ul/G5
/ cGTodf Pp6} r]gnaf6 k;| f/0f ul/G5 .

PlDNfRo8' df]8o\ 'n;] g (Amplitude cfjl[ Q df8] o\ 'n];g (Frequency

modulation-AM_ modulation-FM)

o;df cl8of] ;ª\st] -audio signal_ nfO{ o;df cl8of] ;ª\st] nfO{ jfxs ;ªs\ ]t
jfxs ;ªs\ ]t -carrier signal_ cg';f/ jfxssf] -carrier signal_ cg;' f/ jfxssf] PDklnr8'
cjl[ Q l:y/ /fvL PlDNfRo8' kl/dfhg{ ul/G5 . l:y/ /fvL cfj[lQ kl/dfh{g ul/G5 .

PDklnr8' df8] o\ n' ;] gaf6 dWod tyf nfdf] cfj[lQ df8] o\ n' ];gaf6 l;h{gf

t/ª\u nDafO ePsf t/ªu\ x¿ k|;f/0f ul/G5 . ul/Psf t/ª\x¿sf] cfjl[ Q a9L x'g] ePsfn]

pbfx/0fsf nflu AM /]l8ofs] f] cfj[lQ bfo/f jfod' 08nsf] cfof]lgs txaf6 k/fjt{g

-frequency range_ 535 kHz b]lv 1705 kHz xbF' }gg\ . a9L cfj[lQ -high frequency_ ePsf

;Dd xG' 5 . /]l8of] k|;f/0fdf o:tf t/ª\ux¿ t/ª\ux¿dfk{mt k;| f/0f xg' ] TV, FM /l] 8ofs] f]

jfod' 08nsf] cfof]lgs txaf6 ;lhn} k/fjt{g k;| f/0f lglZrt b/' L;Dd ;Lldt /xG5, h'g

xG' 5g\ / 6f9f;Dd k;| f/0f x'G5g\ . P=Pd= e"agf6] tyf 6«fG;ld6/ 6fj/sf] prfOdf e/

k|;f/0fdf afXo jftfj/0fsf] k|efj k5{ . k5{ . o:tf] k|;f/0f k|:6 ;G' g ;lsG5 . FM

To;}n] o;sf] k|;f/0f lbgsf] ;dodf eGbf /]l8of]sf] cfjl[ Q bfo/f -frequency range_

/ftsf] ;dodf k|:6 ;l' gG5 . 88 MHz bl] v 108 MHz x'G5 .

214 lj1fg tyf k|ljlwM sIff (

lj|mofsnfk 13.9

sIffdf 5nkmnaf6 /]l8of,] 6l] nlehg, 6]lnkmf]g, km\ ofS;, df]afOn kmfg] , jfOkmfO, Odn] ,
OG6/g6] / lhlkP; ;ad} f b/" ;~rf/ k|ljwsf cjojx¿ 5'6o\ fpg'xf];\ / ;DalGwt pks/0fx¿sf
gfd tnsf] h:t} tflnsfdf egx'{ f;] \ . s] oL ;a}sf] ko| f]u b/" ;~rf/ kl| jlwcGtu{t k5{ < lsg,
5nkmn ugx{' f];\ .

b/" ;~rf/sf k|ljlwx¿ 6«fG;ld6/ Rofgn -tf/, t/ª\u, clK6sn kfOa/_ l/l;e/

6]lnlehg k|;f/0f ================= ======================== =============

/]l8of] k|;f/0f ================ ======================== ==============

==================== ================ ======================= ==============

kl/of]hgf sfo{

:yfgLo ¿kdf pknAw ;fduL| x¿sf] ko| f]uaf6 b"/;~rf/ kl| jlwsf sfo{ l;4fGt kb| zg{ ug{
/]l8of]÷6l] nlehg k|;f/0fsf] gd'gf tof/ kfg{x' f];\ .

cfwl' gs ;~rf/ kl| jlwsf ¿kdf OG6/g6] (Internet as a modern communication tool)

lj|mofsnfk 13.10

;do;u“ } kl| jlwsf] ljsf;n] ;~rf/ kl| jlwdf cfPsf] kl/jt{gaf/] vf]hL ug'x{ f];\ . ljleGg
;~rf/sf ljm| ofsnfksf k'/fgf tl/sf / jt{dfg ;dodf OG6/g6] sf] ko| f]u ul/g] ;DalGwt
;~rf/sf tl/sfx¿ tnsf] h:t} tflnsfdf eg'{xf];\ . cGTodf 5nkmnaf6 o; ljm| ofsnfksf]
lgisif{ n]Vg'xf;] \ .

;~rf/sf klxn] -OG6/g]6sf] cfhef]nL -OG6/g6] sf] lj:tf/ kZrft_ sf] tl/sf
lj|mofsnfk lj:tf/ kj" _{ sf] tl/sf tl/sf k|ofu] ul/g] ;~rf/ 6n' kmfObf

-communication tool_

lr7L÷;"rgf xn' fs, k\mofS; lhd]n -Gmail_
k7fpg

s'/fsfgL ug{ ================ ;fdflhs ;~hfn
-====, ===_, d;] ]Gh/

================ ================ ============ ================ ================

sDKo'6/, :df6{ kmf]g / OG6/g6] k|ljlwsf] ljsf;F+u} ;~rf/ ljm| ofsnfksf tl/sf kl/jtg{ x'Fb}
cfPsf 5g\ . OG6/g6] sf] k|of]uaf6 6l] nkmfg] tyf dfa] fOn kmfg] snsf] ;6\6f >Job[Zo OG6/g6]
sn - Audio/video internet call _ ug{ ;lsG5 . d"Nosf lx;fan] cgnfOg sn lgs} ;:tf] x'G5 .
To:t} lr7L, km\ ofS; k7fpg'sf] ;66\ f Odn] -electronic mail_ k7fpg ;lsG5 . Odn] af6 ul/g]

lj1fg tyf k|ljlwM sIff ( 215

;~rf/ tLj| / ljZj;gLo x'G5 . dflg;x¿ sfuhL klqsfx¿sf] ;6\6f OG6/g6] sf dfWoodaf6
cgnfOg ;dfrf/ k9g\ ;S5g\ . cgnfOg ;dfrf/x¿ sg' } gofF 36gf 36\g] ljlQs} k;| fl/t u/L
kf7s;Dd k¥' ofpg ;lsG5 . s]an l6eLsf] :yfgdf OG6/g]6 l6eL -IPTV-Internet Protocol
Television_ sf] k|ofu] ug{ ;lsG5 . OG6/g]6 l6eLaf6 k|;fl/t >JobZ[ o ;fdu|L lgs} u'0f:t/
-High Quality_ sf] x'G5 . dfly pNnv] ul/Psf lj|mofsnfkx¿df OG6/g]6sf] ko| f]u ;~rf/df
cfwl' gs kl| jlwsf] k|ofu] sf s]xL pbfx/0fx¿ x'g\ .

ljm| ofsnfk 13.11

bO' { b'O{ hgfsf] ;d"xdf tn lbOPsf r/0fx¿sf cfwf/df lhd]n csfpG6 l;hg{ f ug{'xf];\ .
To;kl5 Psn] csf{nfO{ Odn] k7fpgx' f;] \ / ;fyLn] k7fPsf] Odn] rs] ug{x' f];\ .

1. tkfO{Fsf] sDKo'6/sf] l:j|mgdf ePsf] a|fph/ cfOsg -pbfx/0fsf nflu j|mfd] - _ df 8an
lSns u/L o;nfO{ vfN] gx' f];\ . o;sf] ;r{ af/ -search bar_ df lSns ug'x{ f;] \ / www.
gmail.com 6fOk ug{'xf;] \ .

2. ljG8fd] f b]lvPsf] ljm| P6 Pg csfpG6 -create an account_ df lSns ug'{xf;] \ .

3. gofF v'Ng] ljG8fd] f uP/ vfnL sf]7fx¿df dfluPsf ;Dk"0f{ ljj/0fx¿ egx{' f];\ . Username_
/ Password kg' M rflxg] ePsfn] cfk"mn] ;lDemg ;Sg] u/L /fVg'xf];\ . cGTodf next df
lSns ugx'{ f;] \ .

4. ljG8fd] f cfk"mn] eg'k{ g{] kmf]g gDa/nufotsf hfgsf/Lx¿ egx'{ f];\ / gS] :6 lyRg'xf];\ .
To;kl5 lhdn] sf sx] L ;tx{ ¿ b]lvg] 5g\ . l:j|mgnfO{ :jm| fn] -scroll_ ub{} tn hfg'xf];\ /
cGTolt/ bl] vg] cfO{= cuL| -I agree_ df lSns ug'{xf];\ . o;/L tkfOsF{ f] hLd]n csfpG6
tof/ xG' 5 .



216 lj1fg tyf kl| jlwM sIff (

5. cfkm\ gf] csfpG6af6 aflx/ cfpg ;fOg cfp6 -sign out_ ug{k' 5{ . o;sf nflu lrqdf
bv] fOP h:t} l:jm| gsf] bfofF s'gfsf] dflyNnf] efudf /xs] f] j[Qdf lSns u/L b]lvg] ;fgf]
ljG8fd] f ePsf] ;fOg cfp6df lSns ugx{' f];\ .

6. cfkm\ gf] lhdn] csfpG6af6 d]n k7fpg' k/d] f ;j{ky| d lhd]n vf]n]/ ;fOg Og -Sign
in_ ugk{' 5{ . o;sf nflu cfk\mgf] Odn] cfO8L -Email ID- …….. @gmail.com_ 6fOk
ug'{xf];\ / g]S:6df lSns ug{x' f];\ . To;kl5 kf;j8{ 6fOk u/L ;OgOg -Sign in_ ug{'xf];\ .
tkfOFn{ ] cfk\mgf] Od]n ljG8f] v'n]sf] b]Vg'xg' ] 5 .

7. cfkm\ gf] Odn] csfpG6af6 ;fyLnfO{ dn] k7fpg tkfOsF{ f] lhdn] sf] ljG8fs] f] afofF 6K' kfs] f] efult/
bl] vg] sDkfh] -compose_ df lSns ugx{' f;] \ . To;kl5 Ps ;fgf] ljG8f] vN' 5 . pSt ljG8fd] f
tn lrqdf bv] fOP h:t} ;fyLsf] dn] cfO8L -……@gmail.com jf ………[email protected]_,
ljifo -subject_ /fv/] ;Gbz] nV] gx' f;] \ . cGTodf ;G] 8 -send_ a6gdf lSns ugx{' f;] \ .

lj1fg tyf k|ljlwM sIff ( 217

8. tkfO{Fsf ;fyLn] k7fPsf] d]n cfk\mgf] d]n aS;af6 x]g{sf nflu sDkfh] ;uF } /xs] f]
Og aS; -Inbox_ lSns ug{x' f;] \ . To;kl5 bl] vg] ;fyLsf] d]ndf lSns u/L To;nfO{ k9\g
;Sg'x'G5 .

OG6/g]6sf] ko| f]uaf6 cWoog ;fdu|Lx¿sf] vfh] (Use of internet to find study materials)

lj|mofsnfk 13.12

OG6/g6] df u'un ;r{ OlGhg -google.com.np_ df tn lbOPsf ;r{ ck/6] /x¿sf] k|of]u u/L
cWoog ;fdu|Lx¿ vfH] gx' f;] \ / vfh] tyf 5nkmnaf6 ltgsf] cflwsfl/stf kQf nufpg'xf;] \ .
tkfOn“{ ] vfH] g' ePsf ;fdu|LnfO{ slk/fO6 nfUg]÷gnfUg] kQf nufpg'xf;] \ . tkfOn“{ ] vfH] g' ePsf
s'g} ljifj:ts' f] l;sfO;u“ ;DalGwt cflwsfl/s ;duL| x¿ -text and images_ ;Dkfbg u/L
kfj/kfO] G6÷lkh| G6;] g k|fu] |fddfkm{ t 8sd' G] 6 tof/ kfgx{' f];\ . cfkm" n] tof/ kf/s] f ;du|LnfO{
sIffdf k|:tt' ugx{' f];\ .

tflnsfM u'un ;r{ ck/]6/x¿sf] k|ofu] -Use of google search operators_

;r{ vf]h ljm| ofaf6 kb| zg{ ug{ rfx]sf ljifo j:t'x¿ ;DalGwt pbfx/0f
ck/6] /
vfh] L ljzi] fsf] j]a;fO6af6 k|sflzt ;fduL| x¿ site:moecdc.gov.np
site:
inurl: vf]hL ljzi] fsf zAb ePsf] lnªs\ inurl:firewall
*:
or vfh] L ul/Psf] zAbx¿ ePsf j]a;fO6x¿ *:firewall

and vf]hL ul/Psf] klxnf] zAb jf bf;] |f] zAb cyjf inurl:firewall or antivirus
-
b'j} zAb
""
filetype: vf]hL ul/Psf klxnf] / bf;] f| ] b'j} zAb inurl:firewall and antivirus

map: s'g} bO' { ;F+u;+uF } cfpg] zAbx¿af6 Pp6fsf af/]df inurl:firewall -antivirus
weather:
dfq

ckm" n] vf]hs] f zAbx¿ l7s p:t} ePsf ja] ;fO6x¿ "cyber bullying in nepal"

cfjZos hfgsf/L ePsf] sg' } ljzi] f lsl;dsf] cyber bullying in nepal
kmfOn h:t} j8{ kmfOn -docx_, kfj/ KjOG6 filetype:docx

-pptx_, lkl8Pkm -pdf_

;DalGwt gS;faf/] hfgsf/L ;d]l6Psf j]a;fO6 map:rara lake

;DalGwt :yfgsf] df};d;DaGwL hfgsf/L weather:bidur

;d]l6Psf ja] ;fO6

;r{ OlGhg -search engine_ Ps OG6/g6] df ePsf j]akh] df /flvPsf hfgsf/Lx¿af6
ko| f]ustf{n] vfh] s] f hfgsf/L ePsf kh] x¿nfO{ 5fg/] ltgsf] ljj/0f kb| z{g ul/lbg] ;k\m6jo/
k0| ffnL xf] . u'un ;r{ OlGhg, laª ;r{ OlGhg -www.bing.com_ o;sf pbfx/0fx¿ xg' \ . ;r{

218 lj1fg tyf kl| jlwM sIff (

OlGhgdf ul/g] kl/:st[ vf]hn] cfjZos ljifoj:t;' Fu ;DalGwt ;fduL| dfq kb| zg{ x'g] ePsfn]
sd ;do nlIft vf]h ;Dej x'G5 . o;/L vf]hL ubf{ cflwsfl/s / slk/fO6 nfUg÷] gnfUg]
;fdu|L 5'6\ofpg ;xh xG' 5 . s'g} zl} Ifs ;:+ yf jf cGo cflwsfl/s ;+:yfn] OG6/g]6df
ckm\ gf] O{k':tsfno -lib.moecdc.gov.np_ leq /fvs] f ;fduL| x¿ kd| fl0ft u//] /flvPsf xG' 5g\ .
cGTodf .edu, .gov, .org, .com ePsf j]a;fO6x¿ sg' } cflwsfl/s ;ª\3 ;:+ yfaf6 ;~rflnt
xg' ] ePsfn] logdf k|sflzt ;fduL| x¿ k|foM cflwsfl/s xG' 5g\ . k|sflzt ljifoj:ts' f] ldlt,
kl/dfhg{ eP÷gePsf,] kf7sx¿n] u/s] f sdG] 6 tyf k[i6kfi] f0f x]//] cfkm" n] OG6/g]6df vfhL
u/s] f ;fdu|Lsf] cflwsfl/stfaf/] hfgsf/L kfpg ;lsG5 .

OG6/g]6df vf]lhPsf cWoog ;fduL| nfO{ k|ofu] ug{ gldNg] cyft{ \ slk/fO6 nfUg] ePdf To:tf
j:tx' ¿nfO{ cGo s'g} klg 7fpFdf k|of]u ug{ kfOFbg} . pbfx/0fsf nflu u'un a'S;df -books.
google.com.np_ df /flvPsf as' x¿df slk/fO6 nfU5 . o;df ePsf lstfax¿ s]an k9\g
ldN5 . lstfadf ePsf lrq, jfSo, cflb cGt st} ko| f]u ul/Pdf slk/fO6 ePsf] JolStn]
rf]/L d2' f btf{ ubf{ k|of]ustfn{ ] ;hfo ef]Ugk' 5{ . s]xL ja] ;fO6x¿n] lgz'Ns k|ofu] ug{
;lsg] ;fdu|L egL pNnv] u/]sf x'G5g\ . pbfx/0fsf nflu km] 6 l;dn' ];g -https://phet.
colorado.edu/ _ df k|sfl;t ;fduL| x¿df slk/fO6 nfUb}g . OG6/g]6df ;r{ u/s] f slk/fO6
gnfUg] ;fduL| x¿ cfk"mn] ;fef/ lnP/ kh| G6];g tof/ kfg'{ k/d] f pSt ;fdu|L;+uF } To;sf] ;|f]t
vn' fpgk' 5{ . pbfx/0fsf nflu s'g} j]a;fO6af6 lrq ;fef/ lnPdf pSt lrqsf] tn ;f| ]t 6fOk
u//] ja] ;fO6sf] gfd n]Vgk' 5{ .

cgnfOg ;'/Iff pkfox¿ (Online security measures)

lj|mofsnfk 13.13

tn lbOPsf a'Fbfx¿ ;d]6]/ Pp6f kfj/ kfO] G6 k|]hG6;] g jf rf6{ tof/ kfg{'xf];\ / sIffdf
k|:t't ug'{xf];\ .

-c_ cgnfOgdf k|lji6 -entry_ ul/g] JolStut ljj/0fx¿sf] uf]klgotf

-cf_ cgnfOgdf ljleGg pd/] ;d"xsf dflg;x¿;Fu xg' ] u/s] f c;fdflhs lj|mofsnfkx¿

-O_ sg' } JolStn] u/s] f cgnfOg ljm| ofsnfk;DaGwL ;/' lIft /xg] kd| f0fx¿ h'g rfxs] f] v08df
kQf nufpg ;lsG5 .

OG6/g6] sf] kx'rF / k|of]u a9\bf] 5 . o;;Fu} k|of]ustfd{ f cgnfOg ;/' Iff af/s] f] hfgsf/Lsf]
cfjZotf klg a9s] f] 5 . cgnfOg ;'/Iff eg]sf] OG6/g]6df ;]o/ -share_ tyf e08f/ ul/Psf
8f6f jf hfgsf/Lsf] ;'/Iff ug{' xf] .

;fdflhs ;~hfndf ;]o/ ul/g] kmf6] f, To;df 6fOk ul/g] ;Gb]zx¿, kf;j8,{ OG6g]6 a}ª\lsª
ko| fu] ubf{ /fVg] kf;j8{, ljleGg lsl;dsf ja] ;fO6df el/g] cgnfOg kmd{ -online form_,
Od]n kf;j8,{ cflbsf] b'¿kof]u ePdf ;d:of l;h{gf x'G5 . OG6/g6] a|fph/ xo\ fs -browser

lj1fg tyf kl| jlwM sIff ( 219

hack_ x'g', JolStut ljj/0f rf/] L xg' ' cflb sdhf]/ cgnfOg ;/' Iffsf pkh xg' \ . h;n] ubf{
JolStut ljj/0f rf]/L u/L ;DalGwt JolStnfO{ cftªls\ t ug,{] a}ªl\ sª\ ljj/0fx¿ rf]/L u/L
vftfaf6 k};f rf]/L xg' ' h:tf 36gfx¿ 36\g ;S5g\ .

cgnfOg ufk] lgotf hf“r (Online privacy checking)

cgnfOg ;l' jwfsf nflu k|of]u ul/g] j]a;fO6 ;/' lIft lrq 13.25 jj] ;fO6sf] ;'/Iff ;l6l{ kms]6 hf“r
x'gk5{ . cgnfOgdf JolStut ljj/0f k|lji6 ugk'{ "j{
ja] ;fO6sf] cflwsfl/stf tyf ;/' Iff hfFr ugk'{ 5{ .
;/' Iff ;l6l{ kms]6af/] hfgsf/L yfxf kfpg lrq 13.25
df bv] fOP h:t} ja] ;fO6sf] 7]ufgf cufl8sf] tnfsf]
;ª\s]tdf lSns ug{x' f];\ . To;kl5 bl] vg] kk ck ljG8f]
-window_ df pSt j]a;fO6sf] kd| f0fLs/0f / To;df
cfkm\ gf] JolStut ljj/0fx¿ /fVg' ;'/lIft /x] g/x]sf]
af/]df pNn]v ul/Psf] xG' 5 .

cgnfOgdf pkxf/, lr67\ f cflbsf gfddf ljj/0f eg{
k7fOg] lnªs\ x¿, ;fdflhs ;~hfndf k7fOg] cgfjZos lnªs\ x¿ ;a} ;/' lIft gx'g ;S5g\ .
o:tf lnªs\ x¿df lSns ubf{ jf ;DalGwt j]a;fO6df ljj/0f ebf{ ;"rgfx¿ rf/] L x'g] ;Defjgf
xG' 5 . sg' } lsl;dsf cgnfOg kmd{ eg'{ k/d] f j]a;fO6sf] cflwsfl/stf kQf nufpgk' 5{ . sg' }

j]a;fO6df ;Og Og -Sign in_ sf] ko| fh] g k/" f eO;s]kl5 To;af6 ;fOg cfp6 -Sign out_
ugk{' 5{ .

;fOa/ a'lnª ;rt] gf (Cyberbullying awareness)

;fOa/ a'lnª ;r" gf tyf ;~rf/ kl| jlwsf] b¿' kof]u xf] . OG6/g]6sf

dfWodaf6 On]S6«f]lgs pks/0fx¿ h:tM} df]afOn kmfg] , sDKo6' /,

6\ofAn6] x¿ ko| f]u u/L sg' } JolSt ljz]ifdf dfgl;s tfgj l;hg{ f

ug{] u/L x'g] ljm| ofsnfk ;fOa/ lrq 13.26 ;fOa/ a'lnª

al' nªcGtut{ k5{g\ . OG6/g]6sf dfWodaf6 s;}sf] JolStut ljj/0f ;fjh{ lgs ug]{ wDsL

lbg,] JolStnfO{ 8/fpg], cZnLn ;fduL| o'St ;Gbz] x¿ k7fpg,] JolStdf xLgtf af]w u/fpg,]

cgnfOgdf JolStsf af/]df cgfjZos xNnfx¿ lkmhfpg] h:tf ljm| ofsnfk ;fOa/ a'lnªsf

pbfx/0fx¿ x'g\ .

lszf]/lszf]/L;uF ul/g] ;fOa/ al' nª k|foM ;fdflhs ;~hfn, d];G] h/, Od]n cflbsf] ko| f]uaf6
x'G5 . ;fOa/ a'lnªuaf6 hfl] ug ;fdflhs ;~hfndf hf] ;s' }nfO{ ;fyLsf ¿kdf l:jsfg'{ xF'b}g .
cgnfOgdf s/' f ubf,{ ;Gb]z k7fpbF f JolStut ljj/0f, ufK] o s/' fx¿ hfgsf/L u/fpg' x'bF g} .
;fdflhs ;~hfndf cfkm" n] ;o] / u/s] f kmf6] f, tyf cGo ljj/0fx¿ ;/' lIft ugk{' 5{ . olb sg' } JolStn]
;fOa/ al' nªsf ljm| ofsnfk ug{ vfh] d] f To;sf] /s] 8{ /fvL cleefjsnfO{ hfgsf/L u/fpgk' 5{ .

220 lj1fg tyf k|ljlwM sIff (

l8lh6n k'm6lkG| 6 ;rt] gf (Digital footprint awareness)

l8lh6n k'm6lk|G6 ljleGg lsl;dsf OnS] 6«f]lgs pks/0fx¿dfk{mt
OG6/g]6sf] ko| fu] ubf{ l;h{gf xg' ] 8f6f k|df0f xf] . xfdLn]
x/] ]sf j]a;fO6x¿sf] ljj/0f, k7fpg] Od]nx¿sf] ljj/0f, cgnfOg
;'ljwfsf nflu k]; ug{] hfgsf/Lx¿, ;fdflhs ;~hfndf ul/g]
nfOs, ;o] /, sd]G6, n]lvg] :6]6;, cflbsf] k|df0f /x]sf] xG' 5 . To:tf
kd| f0fx¿ rfxd] f vf]Hg ;lsG5 . pbfx/0fsf nflu sg} ckl/lrt
JolStn] j]a;fO6dfk{mt u/s] f lj|mofsnfkx¿sf cfwf/df OG6/g]6 lrq 13.27 l8lh6n k'm6lkG| 6
;j] f kb| fosn] lbg] cfOkL 7u] fgf -IP address_ x]/L pSt JolStsf]
7u] fgf kQf nufpg ;lsG5 . To:t} s'g} JolStn] ;fdflhs ;~hfn cftªs\ l;hg{ f ug]{ ;fduL|
/fv]/ kl5 pSt ljj/0f x6fP klg Tof] ;fdflhs ;~hfnsf] 8f6fjz] df ;'/lIft /xG5 . o;/L
e]l6Psf] kd| f0fs} cfwf/df pSt JolStnfO{ kx| /Ln] klj|mg ;S5 .

OG6/g6] ;l' jwfsf nflu ko| fu] u/s] f pks/0fx¿df JolStn] x/] s] f lrq 13.28 af| plhª lx:6L«
ja] ;fO6x¿sf] ljj/0f ;/' lIft /xs] f] xG' 5 . To:t} JolStn] e/s] f kf;j8{ klg x6fOPsf]
e08f/ eP/ /xg ;S5g\ . o;nfO{ x6fpgsf nflu OG6/g6] sf] ko| fu] kZrft\
af| ph/ -browser_ sf] lx:6L« -history_ df uP/ Sof; -cache_ nfO{ ;kmf
-clear_ ugk{' 5{ . JolStut pks/0fafxs] cGo pks/0fdf OG6/g6] ko| fu]
ubf{ ja] ;fO6dfkf;j8{ ;e] -save_ ug{ rfxgx' G' 5 < eGg] ;Gbz] cfPdf ;e]
ugx{' b'F g} .

kmfo/jfn / PlG6efO/; ;'/Iff (Firewall and antivirus protection)

lj|mofsnfk 13.14

tkfO“s{ f] sDKo6' /sf] ;r{ aS;df kmfP/jfn -Firewall_ 6fOk u/L vfH] gx' f];\ . kmfo/jfn cg
/ ckm u/L xg] {x' f];\ . pSt kmfo/jfnaf/] n]lvPsf ljj/0fx¿ k9L o;sf] sfo{af/] 5nkmn
ug{'xf;] \ . pSt sDKo6' /df PlG6efO/; ;km\ 6jo/ /flvP g/flvPsf] cjnfs] g ug'x{ f;] \ .
sDKo6' / PlG6efO/;sf] k|of]usf sf/0fx¿af/] 5nkmn ug{x' f];\ . OG6/g6] sf] k|of]u u/L ljleGg
7fpFdf ePsf ;fOa/ c6o\ fs -cyber attack_ sf pbfx/0fx¿ vfh] L ug{x' f];\ .

kmfP/jfn -Firewall_ PlG6efO/;sf] ko| fu] sf ;fOa/ c6\ofs -cyber attack_
sf] sfo{ sf/0fx¿ sf pbfx/0fx¿

====================== ======================================= ===================================

sDKo6' / g6] jlsª{ -OG6/g]6_ af6 8f6f cfbfg k|bfgsf j|mddf xflgsf/s 8f6f tyf cgflws[t
g6] jlsª{ ;ª\s]tnfO{ 5S] g] -block_ / ;'/lIft 8f6fnfO{ dfq cfkm\ gf] sDKo'6/;Dd cfpg lbgsf
nflu kmfo/jfn -firewall_ rflxG5 . ;km\ 6jo/df cfwfl/t kmfo/jfn sDKo6' /ddf ck/]l6ª

lj1fg tyf k|ljlwM sIff ( 221

;k\m6jo/ -operating software eg. Ms Windows_

;+Fu Olg:6n -Install_ ePsf] x'G5 . o;nfO{ ;w}F cg

u//] OG6/g6] sf] ko| fu] ugk{' 5{ . aª} s\ 8f6f ;e{/

-data server_ tyf sx] L ;ª3\ ;:yfx¿sf ja] ;fO6

8f6fa;] -database_ df yk' |} JolStsf JolStut

ljj/0fx¿ /x]sf x'G5g\ . Pl6Pd x\oflsªaf6 x'g]

k;} f rf/] L, j]a;fO6 x\folsªaf6 xg' ] 8f6f rf/] L cflb lrq 13.29 sDKo6' / g]6jlsª{ / kmfo/jfn
sdhf]/ kmfo/jfn (Firewall_ sf glthf x'g\ . o:tf

ljm| ofsnfkx¿nfO{ ;fOa/ c6\ofs -cyber attack_

elgG5 . g]kfndf klg o:tf 36gfdf ;fdn] JolStx¿ k|sfp k/]sf pbfx/0fx¿ 5g\ .

sDKo6' / efO/; Ps kf| u] |fd xf] . of] sDKo6' / ;~rfng ug]{ kf| u] |fddf ldl;P/ cfkm\ gf kl| tlnlkx¿
agfp5F / cfjZos kf| u] fdx¿nfO{ ;ªj\ m| ldt ub5{ . o;n] lj:tf/} sDKo6' /nfO{ cfkm\ gf] k|fu] f| dsf
cfwf/df lgb]z{ g lbg yfN5 . h;n] ubf{ efO/; ;ª\jm| ldt sDKo'6/df sg' } k|f]u|fd cfkm} F v'Ng],
sx] L 8f6fx¿ l8ln6 x'g,] sDKo'6/sf] dd] f/] Ldf ;r" gf kz| f]wgsf nfUg] ;dodf l9nf] xg' ] h:tf
;d:of bv] f k5g{ \ .

sDKo'6/ efO/; cfkm} F Ps sDKo'6/af6 csf{] sDKo6' /df ;b{g} . Pp6f efO/; ;ª\j|mldt
sDKo6' /af6 csf]{ sDKo'6/df 8f6f ;fbf{ cb[Zo ¿kdf efO/;sf] kmfOn klg ;b5{ . OG6/g]6sf]
ko| f]u ubf{ s'g} cgflwsfl/s ja] ;fO6 -website_ af6 sDKo6' /df cfpg] 8f6f;Fu} efO/; kj| z]
ug{ ;S5 . sDKo6' / ;/' Iffsf nflu o;df efO/;sf] kj| ]z ePdf To;sf] vf]hL u/L x6fpg ;Sg]

u/L Olg:6n ul/Psf] kf| u] |fd PlG6efO/; -antivirus_

xf] . o;nfO{ OG6/g]6 jf cGo dfWod h:t} kg] 8«fOa -pen drive_ af6 sDKo6' /df cfPsf efO/;nfO{
kQf nufpg, 5'6o\ fpg / ltgnfO{ x6fpg k|of]u ul/G5 . pbfx/0fsf nflu dfOj|mf];k\m6 ljG8fh]
l8km] G8/ -Microsoft Defender _ sDKo'6/df ljG8fh] /fVbf kf| Kt xg' ] PlG6efO/; ;k\m6jo/ xf] .
ahf/df lsg]/ cGo PlG6efO/; ;k\m6jo/x¿ klg sDKo'6/df Olg:6n ug{ ;lsG5 .

kl/ofh] gf sfo{

-s_ OG6/g]6sf] c;/' lIft ko| f]un] ubf{ 36s] f ljleGg lsl;dsf 36gfx¿af/] cWoog ug{'xf;] \ .
tL 36gfx¿sf sf/0f / To:tf 36gf kg' M 36g\ glbg ckgfpg'kg]{ ;fjwfgLaf/] vf]hL
ug'{xf];\ . cfkm\ gf] cWoogaf6 k|fKt hfgsf/Lx¿ nfO{ l/kf]6s{ f ¿kdf k:| tt' u/L sIffdf
5nkmn ug'x{ f];\ .

-v_ gk] fndf 36\g] sx] L dV' of ;fOa/ ck/fw -cyber crime_ x¿dWo] Pl6Pd cfjm| d0f -ATM
attacks), g:ko] / lkml;ª (spear phishing), uf]kgLotf rx' fj6 (privacy leaks) /
;fdflhs ;~hfn ck/fwx¿ h:t}M pTkL8g -harassments) klxrfg rf/] L -identify
theft), ckmjfxx¿ k}mnfpg] (dissemination of false information) cflb . oL 36gfx¿sf
pbfx/0f vf]hL u/L Ps cWoog l/kf6] { tof/ kfg'x{ f];\ .

222 lj1fg tyf k|ljlwM sIff (

cEof;

!= ;xL pQ/ 5fGgx' f;] \ M
-s_ ep" kux| nfO{ s'g sIfdf k|Ifk] 0f ubf{ ;wF} kY[ jLsf] ed" Wo /v] Lo efu dflysf] cfsfzdf
;fk]lIfs ¿kdf l:y/ /xg] u/L 3'ld/xG5 <
-c_ lgDg kY[ jL sIf -low earth orbit_ -cf_ dWod kY[ jL sIf -medium earth orbit_
-O_ e":yfoL sIf -geostationary orbit_ -O_{ lhofl] ;Gjm| fg] ; sIf -geosynchronous orbit_
-v_ /]l8of] t/ª\u k;| f/0fsf nflu lrqdf b]vfOPsf] df]8\o'n];g;Fu ldNg] ljzi] ftf s'g
xf] <

-c_ k|;fl/t t/ªx\ ¿sf] cfj[lQ a9L xG' 5 .

-cf_ k|;fl/t t/ªu\ x¿ jfo'd08nsf] cfof]lgs txaf6 ;lhn} k/fjtg{ xG' 5g\ .

-O_ k;| fl/t t/ª\u lglZrt b/' L;Dd l;ldt /xG5g\ .

-O{_ k;| f/0fdf afxo\ jftfj/0fsf] k|efj kbg{} .

-u_ tkfOn{F ] ;r{ OlGhg -search engine_ sf] ko| fu] af6 jg:klt tGt' -plant tissue_ sf
af/d] f kfj/ kf]OG6 lk|hG6];g :nfO8 vfH] g' k/d] f s'g l;G6fS; -syntax_ pko'St
xG' 5 <

-c_ filetype:plant tissue.pptx -cf_ plant tissue filetype.pptx

-O_ plant tissue filetype:pptx -O_{ filetype plant tissue:pptx

-3_ Odn] -e-mail_ eGgfn] s] a'lemG5 <

-c_ Od/h]G;L dn] -emergency mail_ -cf_ OnS] 6f« ]lgs d]n -electronic mail_

-O_ cln{ d]n -early mail_ -O{_ Okm] lS6e dn] -effective mail_

-ª_ sg' } ljBfyL{n] ;fdflhs ;~hfndfkm{ t ;fyLnfO{ wDsfpg] ;Gbz] k7fP/ sx] L ;dokl5
pSt ;Gb]znfO{ ;as} f nflu gbl] vg] u/L x6fP / cfk"m ;'/lIft ePsf] 7fg] eg] of]
s'g ;rt] gfsf] sdL xf] <

lj1fg tyf k|ljlwM sIff ( 223

-c_ cgnfOg uf]klgotf -cf_ l8lh6n k'6lkG| 6
-O_ sDKo6' / efO/; -O{_ sDKo'6/ kmfo/jfn
@= km/s nV] gx' f];\ M
-s_ kmfo/jfn -firewall_ / PlG6efO/; -antivirus_
-v_ PDklnr'8 df]8\o'n;] g -amplitude modulation_ / lkm| Sj]G;L df]8o\ 'n;] g -frequency
modulation_
#= sf/0f n]Vgx' f];\ M

-s_ ;;+ f/sf ljleGg b]zx¿n] ;~rf/ ep" ku|xnfO{ e":yfoL sIfdf kI| f]k0f u/]sf 5g\ .
-v_ nfdf] b"/Lsf] k;| f/0fsf nflu cGtl/If t/ª\unfO{ ;~rf/ e"pku|xdf k7fOG5 .
$= tnsf kZ| gx¿sf] pQ/ n]Vgx' f];\ M
-s_ ;r" gf tyf ;~rf/ k|ljlw eg]sf] s] xf] <
-v_ e"pku|xx¿lagf s'g} pmhf{sf] ko| fu] n] s;/L kY[ jLsf] jl/kl/ sIfdf lg/Gt/
3'ld/xG5g\ <
-u_ g]kfnsf] klxnf] ep" ku|xnfO{ s] gfd lbOPsf] lyof] <
-3_ b"/;~rf/sf] egs] f] s] xf] < b/" ;~rf/ kl| jlwsf pbfx/0fx¿ n]Vgx' f;] \ .
-ª_ tkfOF{n] b"/;~rf/ k|ljlwsf] ko| fu] sg' sg' k|of]hgsf nflu ug{x' 'G5 <
-r_ b/" ;~rf/ k|ljlwsf] sfo{ l;4fGt pbfx/0f;lxt JofVof ugx{' f;] \ .
-5_ /l] 8of] t/ªu\ k|;f/0fsf nflu tnsf] lrqdf b]vfOPsf] df]8o\ 'n;] g lrGgx' f;] \ .
o; lsl;dsf] df]8\on' ;] gsf] k|of]hg n]Vg'xf];\ .



-h_ OG6/g]6 ;~rf/ Ps cfw'lgs ;~rf/ k|ljlw xf] . o; egfOnfO{ pbfx/0f;lxt
k'li6 ug{x' f;] \ .

-em_ s;/L OG6/g]6sf] k|ofu] n] 1fg / hfgsf/Lx¿ kf| Kt ug{ ;lsG5 < pbfx/0f;lxt
JofVof ug'{xf;] \ .

224 lj1fg tyf k|ljlwM sIff (

-`_ cgnfOg ;/' Iff eg]sf] s] xf] < cgnfOg ;/' Iffsf pkfox¿ n]Vg'xf];\ .

-6_ OG6/g]6dfkm{ t a}+lsªu sf/fa] f/ tyf ;fdflhs ;~hfn ko| f]u ug{ ;'? u/]sf gofF
k|ofu] stfn{ fO{ cgnfOg ;/' Iffsf af/]df tkfOF{n] lbg' xg' ] d'Vo ;'emfjx¿ sf/0f;lxt
pNnv] ug{x' f];\ .

-7_ lzIffdf ;r" gf tyf ;~rf/ kl| jlwsf] k|of]u zLifs{ df lgaGw nV] g'xf;] \ .

lj1fg tyf k|ljlwM sIff ( 225

!$ k/df0f' ;/+ rgf / /f;folgs aG8
(Atomic Structure and Chemical Bond)

xfd|f] j/k/ ljleGg lsl;dsf kbfy{ kfOG5g\ . tLdWo] sx] L tŒj x'G5g\ eg] afsF L of}lus
x'G5g\ . ;g' , rfbF L, tfdfnufotsf wftx' ¿ / ;Nkm/, cfofl] 8gnufotsf cwft'x¿ tŒjx¿
xg' \ . clxn;] Dd hDdf 118 cf6] f tŒjx¿ kQf nfus] f 5g\ . j1} flgsx¿af6 tŒjx¿sf] vfh] L
ug{] sfd lg/Gt/ rln/xs] f] 5 . tŒjx¿ l;ldt ;ª\Vofdf eP klg tL tŒjx¿af6 nfvf}Fsf] ;ª\
Vofdf ofl} usx¿ ags] f 5g\ . kT| os] ofl} usdf Ps jf PseGbf a9L tŒjsf k/df0fx' ¿ /xs] f xG' 5g\ .

k/df0fs' f] kl/ro (Introduction to an atom)

sg' } tŒjsf] ;ae} Gbf ;fgf] s0fnfO{ s] elgG5 < s] tŒjdf o;eGbf klg ;fgf s0f xG' 5g,\
5nkmn u/fF} .

tŒj Pp6f z'4 kbfy{ xf] . o;nfO{ 6j' |m\ofP/ ofe] Gbf leGg /f;folgs u0' f ePsf] cGo kbfy{
agfpg ;lsFb}g . pbfx/0fsf nflu kmnfd Pp6f tŒj xf] < o;sf] kftfnfO{ 6j' m| o\ fpbF } hfg] xf]
eg] leGg u0' f ePsf cGo kbfy{ agfpg ;lsbF g} . tŒj Ps jf PseGbf w/] } k/df0f'x¿ ldn/]
ags] f] x'G5 . k/df0f' OnS] 6«fg] , kf| 6] f]g / Go'6f« g] ldn]/ ag] klg of] tŒjsf] ;ae} Gbf ;fgf] cleefHo
s0f xf] . ctM /f;folgs kl| tlj|mofdf efu lng] tŒjsf] ;a}eGbf ;fgf] cleefHo s0fnfO{
k/df0f' elgG5 .

clwsfz+ tŒjsf k/df0fx' ¿ cGo tŒjsf k/df0f'x¿;uF /f;folgs kl| tljm| ofdf efu lnG5g\ .
s]xL tŒjsf k/df0fx' ¿ /f;folgs ¿kdf lglZjm| o xG' 5g\ . Pp6} tŒjsf ;a} k/df0f'x¿ ;dfg
x'G5g\ . t/ ljleGg tŒjsf k/df0fx' ¿ Pscfk;df leGg x'G5g\ . pbfx/0fsf nflu Pp6f ;'gsf]
cfF}7Ldf /xs] f ;'gsf ;a} k/df0fx' ¿ ;dfg xG' 5g\ . t/ ;'gsf] k/df0f'eGbf rfFbLsf] k/df0f' km/s
x'G5 . To;} u/L, rfbF Lsf] k/df0fe' Gbf tfdfsf] k/df0f' klg km/s g} x'G5 .

k/df0fs' f] ;/+ rgf (Structure of an atom)

tŒjsf] ;ae} Gbf ;fgf] cleefHo s0fnfO{ k/df0f'

elgG5 . o;sf] cf;} t Jof; nueu 10-10 ld6/

xG' 5 . k/df0f' tLg k|sf/sf cToGt} ;fgf s0fx¿ ldn/]

ags] f] xG' 5 . h;nfO{ pkkf/df0fljs s0fx¿ (sub-atomic

particles) elgG5 . tL s0fx¿ On]S6«fg] (electron) kf| ]6fg]

(proton) / Go'6f« g] (electron) x'g\ . tLdWo] k|f]6f]g / Go6' f« g] lrq 14.1

k/df0f'sf] sG] b| cyf{t Gol' Sno; (nucleus) df /xs] f xG' 5g\ eg] OnS] 6f« ]gx¿ Gol' Sno;sf] jl/kl/

ljleGg ;n] x¿ (shells) cyf{t sIfx¿ (orbits) df tLj| ultsf ;fy 3'ld/x]sf xG' 5g\ .

226 lj1fg tyf k|ljlwM sIff (

lgn af/] sf] k/df0f' ;+/rgf (Neil's Bohr Atomic Model)

k/df0f'sf] ;+/rgfaf/] ;g\ 1915 df lgn af/] n] Pp6f df8] n]

k|:t't ug{'eof] h;nfO{ lgn af/] sf] k/df0f' ;/+ rgf elgG5 .

o; df8] n] cg';f/ k/df0f'sf] sG] bd| f wgfTds rfho{ S' t Gol' Sno;

/x]sf] xG' 5 eg] Go'lSno;sf] jl/kl/ C0ffTds rfh{o'St lrq 14.2 Bohr's Model of an atom

OnS] 6«f]gx¿ lglZrt sIfdf 3'ld/xs] f xG' 5g\ .

lgn af]/n] k/df0f' df]8n] sf ;DaGwdf lgGgfg;' f/ JofVof u/]sf lyP M

-s_ Pp6f k/df0fd' f wgfTds rfh{oS' t Go'lSno; xG' 5 eg] pSt Gol' Sno;sf] jl/kl/ C0ffTds
rfho{ 'St OnS] 6f« g] x¿ lglZrt af6fdf 3'ld/xs] f x'G5g\ . pSt af6fnfO{ ;]n (shell) jf sIf
(orbit) elgG5 .

-v_ x/]s ;n] df lglZrt pmhf{ x'G5 . tL ;]nx¿sf] cfsf/ jQ[ fsf/ xG' 5 .

-u_ sIf (orbit) jf ;n] (shell) nfO{ jm| dzM (n = 1, 2, 3, 4,…) n] hgfOG5 . sIf 1, 2, 3, / 4
nfO{ j|mdzM K, L, M / N n]lvG5 .

-3_ Pp6f k/df0fd' f On]S6f« g] x¿ sd pmhf{ ePsf] ;n] af6 cfjZos pmhf{ kf| Kt u/L a9L pmhf{
ePsf] ;n] df hfg] ub{5g\ . To;u} /L a9L pmhf{ ePsf] ;]naf6 pmhf{ ud' fP/ On]S6f« g] x¿
sd pmhf{ ePsf] ;n] df kj| ]z ug{] ub5{ g\ .

lj|mofsnfk 14.1 k/df0f'sf] gdg' f lgdf0{ f

cfjZos ;fdu|L M :yfgLo ;fduL| x¿ h:t} 9nfg tf/, wfuf], 6]an' 6]lg; an jf df6fsf
;;fgf anx¿ cflb .

ljlw

– kf/df0fljs ;ªV\ of 1 b]lv 20 ;Ddsf k/df0fx' ¿sf] gdg' f Psn jf ;d"xdf tof/ ug{
lhDdj] f/L afF8kmf8F ug{x' f];\ .

– pknAw ;fdu|Lx¿sf] k|ofu] u/L lhDdj] f/Lcg;' f/sf gd'gf tof/ ug{x' f];\ .

– k/df0fx' ¿sf] ;/+ rgfsf] gd'gf cWoog u/L xfO8«f]hgbl] v SoflN;od;Ddsf tŒjx¿sf]
;ª\st] , kf/df0fljs ;ª\Vof / On]S6f« g] ljGof; b]vfO{ tflnsf agfpg'xf];\ .

cjnf]sg / 5nkmn M tof/ ul/Psf gd'gfnfO{ / tflnsf sIffdf k|bz{g ugx{' f];\ . gdg' f /
tflnsfsf cfwf/df kT| o]s tŒjsf] kf/df0fljs ;/+ rgfsf ;DaGwdf 5nkmn ug{'xf];\ .

lj1fg tyf k|ljlwM sIff ( 227

8K' n6] / 8K' n]6 lgod (Duplet and duplet rule)

lxlnodsf] k/df0f'df Pp6f dfq ;]n (K-shell) /xs] f]
x'G5 . K ;n] g} lxlnod k/df0fs' f] klxnf] / clGtd ;n]

xf] . 2n2 lgodcg';f/ K ;n] df hDdf bO' {cf6] f
OnS] 6f« g] dfq /xg ;S5g\ . aflx/L K ;]ndf b'O{cf]6f
dfq OnS] 6«f]g /xg] k/df0f'sf] cj:yfnfO{ 8K' n6] cj:yf
elgG5 . 8K' n]6 cj:yf ePsf] sf/0fn] ubf{ g} lxlnodsf]
k/df0f' /f;folgs ¿kdf lgl:j|mo ePsf] xf] . o;n] s'g} lrq 14.3 Helium atomic structure
klg /f;folgs k|ltlj|mofdf efu lnbF g} . kmn:j¿k lxlnodsf] k/df0f' ks| l[ tdf :jtGq ¿kdf
kfpg ;lsG5 .

xfO8f« ]hg (H), lnlyod (Li), a]l/lnod (Be) h:tf tŒjsf k/df0f'x¿ OnS] 6f« ]g kf| Kt u//] ,
ud' fP/ jf ;fem]bf/L u//] lxlnodsf] h:t} 8K' n]6 cj:yfdf cfpg ;lj|mo ¿kdf /f;folgs
k|ltljm| ofdf efu lng] ub5{ g\ . o;nfO{ g} 8'Kn]6sf] lgod (Duplet rule) elgG5 . ctM k/df0f'sf]
K- ;n] df b'Oc{ f]6f OnS] 6f« ]g ePsf] cj:yfnfO{ 8'Kn]6 (duplet) cj:yf elgG5 eg] K- ;n] df
8'Kn6] k¥' ofO{ /f;folgs ¿kdf l:y/ cj:yf (stable state) xfl;n ug{] lgodnfO{ 8'Kn]6 lgod
elgG5 .

cS6]6 / cS66] lgod (Octet and octed rule)

lxlnod k/df0fa' fx]s lgl:jm| o Uof;sf] ;d"xdf lrq 14.4 Ne, Ar sf] k/df0fx' ¿sf] ;/+ rgf

/xs] f cyf{t\ kl] /of]l8s tflnsfsf] ;dx" 18 df /flvPsf

tŒjx¿ (Ne, Ar, Kr, Xe / Rn) sf] aflx/L ;]ndf 8 cf]6f
On]S6«fg] x¿ /xs] f x'G5g\ . k/df0f'x¿sf] o; cj:yfnfO{
cS6]6 cj:yf (Octet state) elgG5 . cS6]6 cj:yfdf
ePsf k/df0f'x¿ /f;folgs k|ltlj|mofdf efu lnbF }
gg\ / ks| [ltdf Uof;F cj:yfdf kfOG5g\ . To;sf/0f oL

tŒjx¿nfO{ lgl:j|mo Uof;x¿ (inert gases) elgG5 .

cfkmg\ f] ;ae} Gbf aflx/L ;]ndf 8 eGbf sd OnS] 6«f]g ePsf k/df0f'x¿ Ps jf PseGbf a9L
OnS] 6f« ]gx¿ kf| Kt u/]/, ud' fP/ jf ;femb] f/L u//] cS6]6 cj:yfdf cfpg /f;folgs k|ltlqmofdf

efu lng] ub5{ g\ . o;nfO{ g} cS66] sf] lgod (Octet rule) elgG5 . ctM k/df0f'sf] aflx/L
;n] df cf7 cf]6f On]S6f« g] ePsf] cj:yfnfO{ cS6]6 (octet) cj:yf elgG5 eg] aflx/L ;]ndf
cS66] k¥' ofO{ /f;folgs ¿kdf l:y/ cj:yf (stable state) xfl;n ug]{ lgodnfO{ cS6]6 lgod
elgG5 .

228 lj1fg tyf kl| jlwM sIff (

Eofn]G; ;]n (Valence shell) / EofnG] ; OnS] 6f« g] (Valence electrons)

Valence shell

KLM KLM

11pt Valence 17pt
12 No Electron 18 No

lrq g+=14.6 ;f]l8odsf] k/df0f' lrq g=+ 14.6 Snf]l/gsf] k/df0f'

lrq …sÚ df ;f]l8odsf] k/df0f' (sodium atom) lbOPsf] 5 . ;fl] 8odsf] k/df0f'df s'n 11
On]S6«fg] xG' 5g\ . t/ tL ;a} On]S6f« g] x¿ /f;folgs kl| tljm| ofdf efu lnFbg} g\ . o;sf] ;a}
eGbf aflx/L ;]n (M-;n] ) df ePsf] Pp6f OnS] 6f« g] n] dfq /f;folgs k|ltljm| ofdf efu lnG5 .
To;n} ] ;f]l8odsf] M-;]nnfO{ EofnG] ; ;n] / pSt OnS] 6f« g] nfO{ Eofn]G; OnS] 6«f]g elgG5 .
To;u} /L lrq …vÚ df lbOPsf] Snf]l/g k/df0fs' f] M-;n] nfO{ Eofn]G; ;n] elgG5 eg] pSt
;]ndf /x]sf ;ftcf6] f On]S6f« ]gx¿nfO{ EofnG] ; On]S6f« g] elgG5 . ctM k/df0fs' f] ;a}eGbf aflx/L
;n] nfO{ EofnG] ; ;n] (valence shell) elgG5 eg] Eofn]G; ;]ndf /x]sf OnS] 6«f]gx¿nfO{ Eofn]G;
OnS] 6«fg] (valence electrons) elgG5 .

;o+ 'Hotf (Valency)

k/df0f'sf] aflx/L ;]ndf /x]sf Eofn]G; OnS] 6f« ]gx¿ /f;folgs kl| tlj|mofdf efu lng ;Sg]
;Defljt OnS] 6f« ]gx¿ xg' \ . /f;folgs k|ltljm| of x'Fbf oL k/df0fx' ¿n] Eofn]G; OnS] 6«f]gx¿af6
Ps jf a9L OnS] 6«f]gx¿sf] n]gb]g jf ;fem] bf/L ug]{ ub{5g\ . pSt On]S6«fg] x¿sf] ;ªV\ ofnfO{
;o+ H' otf elgG5 . ctM k/df0f'x¿lar ng] bg] jf ;fe]mbf/L xg' ] OnS] 6f« ]gx¿sf] ;ª\VofnfO{
;+o'Hotf ;ª\Vof elgG5 eg] s'g} Pp6f k/df0fs' f] csf]{ k/df0f;' Fu ;o+ fh] g ug]{ IfdtfnfO{
;+o'Hotf cyf{t Eofn]G;L elgG5 .

k/df0fljs ;ª\Vof 1 bl] v 20 ;Ddsf tŒjx¿sf] OnS] 6«fl] gs ljGof; / ;o+ H' otf tnsf] tflnsfdf
lbOPsf 5g\ .

lj1fg tyf kl| jlwM sIff ( 229

tflnsf g= 14.1
tŒjsf] gfd kf/df0fljs ;ª\Vof ;]nsf] cfwf/df On]S6«f]lgs ljGof; ;+oH' otf

K L MN

xfO8f« h] g 11 1

lxlnod 22 0

lnlyod 3 21 1

a]l/lnod 4 22 2

af/] fg] 5 2 3 3

sfag{ 6 2 4 4

gfO6f« ]hg 7 25 3

clS;hg 8 26 2

kmn\ fl] /g 9 27 1

lgof]g 10 2 8 0

;fl] 8od 11 2 8 1 1

DofUgl] ;od 12 2 8 2 2

Pn'ldlgod 13 2 8 3 3

l;lnsg 14 2 8 4 4

km:kmf]/; 15 2 8 5 3, 5

;Nkm/ 16 2 8 6 2, 6

Snfl] /g 17 2 8 7 1

cfu{g 18 2 8 8 0

kf6] fl;od 19 28 81 1

SoflN;od 20 28 82 2

lj|mofsnfk 14.2

Pp6f rf6{kk] /df kf/df0fljs ;ª\Vof 1 b]lv 20 ;Ddsf k/df0f'x¿sf] agf6] sf] lrq
agfpgx' f];\ . ca x/s] k/df0f'sf] Eofn]G; ;n] , EofnG] ; On{ S] 6«fg] / ;+oH' otfsf] tflnsf agfO{
sIffdf 5nkmn ug{'xf];\ .

230 lj1fg tyf k|ljlwM sIff (

;fdfGotof ;+oH' otf ;ª\Vof sd ePsf tŒjx¿ a9L ;lso| xG' 5g\ eg] ;+oH' otf ;ª\Vof a9L
ePsf tŒjx¿ /f;folgs ¿kdf sd ;ljm| o xG' 5g\ . pbfx/0fsf nflu ;fl] 8od, DofUg]l;od /
PlNdlgodsf] ;o+ H' otf j|mdz M 1, 2 / 3 xG' 5 . h;n] ubf{ ;fl] 8od ;ae} Gbf a9L /f;folgs
¿kn] ;ljm| o x'G5 eg] PlNdlgod ;ae} Gbf sd ;lj|mo xG' 5 .

sg' } sg' } tŒjsf] Eofn]G;L PseGbf w/] } x'G5 . pbfx/0fsf nflu kmnfdsf] EofnG] ;L 2 / 3 xG' 5

eg] ;g' (Au) sf] EofnG] ;L 1 / 3 x'G5 . tŒjx¿n] /f;folgs kl| tljm| ofdf efu lng] j|mddf
;ae} Gbf aflx/L ;n] df ePsf OnS] 6«fg] x¿ dfq efu lnP eg] pSt tŒjsf] EofnG] ;L Pp6f dfq
x'G5 . To;}u/L EofnG] ; ;n] eGbf leqsf] ;n] df /x]sf OnS] 6f« ]gx¿ ;d]t /f;folgs kl| tlj|mofdf
efu lnP eg] pSt tŒjsf] ;o+ H' otf csf{] klg xG' 5 . pbfx/0fsf nflu tfdf (Cu) sf] ;o+ 'Hotf
1 / 2 x'g ;S5 . o:tf sx] L tŒjx¿sf] ;o+ H' otf tnsf] tflnsfdf lbOPsf] 5 .

tŒjx¿sf] gfd / ;ªs\ ]t (Names and Symbols of Elements) ;+oH' otf (Valency)

kmnfd (Fe) 2/3

Tffdf (Cu) 1/2

rfFbL (Ag) 1/2

;g' (Au) 1/3

Kff/f] (Hg) 1/2

cfof]g (Ion)

x/]s k/df0f' a/fa/ ;ª\Vofsf wgfTds rfh{o'St k|f]6f]g / C0ffTds rfh{oS' t On]S6f« ]gx¿
ldn]/ ag]sf] xG' 5 . To;sf/0f tŒjsf] k/df0f' ljBt' Lo ¿kdf t6:y (electrically neutral)
xG' 5 . t/ ha k/df0f' jf k/df0f'sf] u'|kn] cfˆgf] EofnG] ; ;]naf6 Ps jf a9L On]S6«f]gx¿
ud' fpF5 jf c¿af6 lnG5, To; cj:yfdf of] k/df0f' rfh{oS' t k/df0f'df ablnG5 . pSt
rfh{oS' t k/df0fn' fO{ cfof]g (ion) elgG5 .

pbfx/0f M Na+, Mg++, Al+++, K+, Ca++, Zn++, Cu+, Cl–, O– –, N– – – cflb . cfofg] x¿df /x]sf]
wgfTds / C0ffTds rfh{nfO{ pSt cfof]gsf] ;o+ H' otf elgG5 eg] OnS] 6«f]gsf] ;ª\Vof ng] bg] sf
cfwf/df cfof]gx¿sf] ;o+ 'Hotf km/s km/s x'G5 .

cfof]gsf lsl;dx¿ (Type of Ions)

Rffhs{ f cfwf/df cfofg] x¿ wgfTds / C0ffTds u/L b'O{ lsl;dsf x'G5g\ .

wgfTds rfho{ 'St cfof]g M ha sg' } tŒjsf] k/df0fn' ] cfˆgf] Eofn]G; ;]naf6 On]S6«f]gx¿
u'dfp5F , of] wgfTds rfho{ 'St cfofg] aGb5 . To;sf/0f EofnG] ; ;]naf6 Ps jf a9L
OnS] 6f« g] x¿ u'dfP/ aGg] cfofg] nfO{ wgfTds rfh{oS' t cfofg] -Sof6fofg] _ elgG5 . s]xL
wgfTds rfh{o'St cfofg] x¿ / ltgLx¿sf] ;+o'Hotf tnsf] tflnsfdf lbOPsf] 5 M

lj1fg tyf kl| jlwM sIff ( 231

;o+ 'Hotf 1 ePsf /l] 8snx¿ ;o+ H' otf 2 ePsf /]l8snx¿ ;o+ H' otf 3 ePsf /l] 8snx¿

/]l8sn ;ª\st] ;q" /l] 8sn ;ª\s]t ;"q /]l8sn ;ªs\ ]t ;"q

xfO8«f]hg H+ al] /lnod Be++ af]/fg] B+++
lnlyod Li+ DofUgl] ;od Mg++ Pnl' dlgod Al+++
;fl] 8od Na+ SoflN;od Ca++ kml] /s Fe+++
kf]6fl;od K+ DofGulgh Mn++ cl/s Au+++
Pdf]lgod NH4+ So'lk|s Cu++
Sok' |; Cu+ d/So'l/s Hg++
l;Na/ Ag+ km]/; Fe++
d/So/' ; Hg+
c/; Au+

C0fTds rfho{ S' t cfof]g M ha sg' } tŒjsf k/df0f'n] c¿ k/df0fa' f6 OnS] 6«fg] x¿ lnG5, Tof]
C0ffTds rfh{o'St cfof]g aGb5 . To;sf/0f c¿ k/df0fa' f6 Ps jf a9L On]S6«fg] x¿ kf| Kt
u/]/ aGg] cfof]gnfO{ C0ffTds rfh{oS' t cfof]g -Pgcfof]g_ elgG5 . sx] L C0ffTds rfh{o'St
cfofg] x¿ / ltgLx¿sf] ;o+ 'Hotf tnsf] tflnsfdf lbOPsf] 5 .

;o+ 'Hotf 1 ePsf /l] 8snx¿ ;o+ H' otf 2 ePsf /]l8snx¿ ;+o'Hotf 3 ePsf /]l8snx¿

/]l8sn ;ªs\ ]t ;"q /]l8sn ;ªs\ t] ;"q /l] 8sn ;ª\s]t ;"q

kmn\ f]/fO8 F– cS;fO8 O– – gfO6f« O8 N– – –
Snf]/fO8 ;NkmfO8 S– – km:km6] PO4– – –
af| d] fO8 Cl– ;Nkm6] SO4– –
cfof]8fO8 sfaf]g{ 6] CO3– –
gfO6«6] Br–
xfO8f« ]cS;fO8
afOsfaf{]g]6 I–
afO;Nkm]6
Snf/] ]6 NO3–
gfO6«fO6 OH–

HCO3–
HSO4–
ClO3–
NO2–

232 lj1fg tyf k|ljlwM sIff (

lj|mofsnfk 14.3

sf8a{ f]8{ k]k/, wfuf,] ud, kf]ts] f /ªu\ Lg bfgf jf bfnsf bfgfx¿ ko| fu] u/L ljleGg
k/df0fx' ¿sf] df8] n] agfpg'xf;] \ . tL k/df0fs' f] df8] ]naf6 wgfTds rfh{o'St cfof]g /
C0ffTds rfh{o'St cfofg] aGg] tl/sf kb| z{g ugx'{ f];\ .

/f;folgs aG8 (Chemical bond)

tnsf lrq x]/f}F / 5nkmn u/f}F M





lrq 14.7

-s_ lrqdf s'g sg' kbfyx{ ¿sf cf0fljs gdg' f b]vfOPsf 5g\ <

-v_ H2 / H2O sf cf0fljs gdg' fx¿lar s] km/s 5 <
-u_ O2 / NaCl sf cf0fljs gdg' fx¿lar s] km/s 5 <
-3_ kfgLsf] c0f';q" H2O / gg' sf] c0f';"q NaCl eP h:t}M nfvfF} of}lusx¿df tŒjx¿
Pscfk;df s;/L aflF 8P/ /xs] f x'G5g,\ ljrf/ ug{x' f];\ .

of}lusdf tŒjsf k/df0f'x¿ ljz]if ks| f/sf] ann] Pscfk;df afFlwPsf xG' 5g\ h;nfO{ /f;folgs
aG8 elgG5 . ;a} of}lusdf Ps} ks| f/sf /f;folgs aG8 xb' }g . tŒjx¿lar /f;folgs
k|ltljm| of eO{ of}lus aGbf tŒjsf k/df0fx' ¿lar Pscfk;df aflF wg Ps ks| f/sf] an nfU5 .
pSt annfO{ g} /f;folgs aG8 (Chemical bond) elgG5 . pbfx/0fsf nflu vfgg] g' sf] c0f'df
/f;folgs aG8n] ;f]l8Pd k/df0f' / Snf]l/g k/df0f'nfO{ Pscfk;df afFw]/ /fv]sf] xG' 5 .

lgl:jm| o Uof;F x¿ (He, Ne, Ar, Kr, Xe / Rn) afx]ssf tŒjsf k/df0fx' ¿ 8'Kn]6 jf cS66]
cj:yfdf /x]sf x'Fbg} g\ . To;sf/0f lgl:j|mo Uof;F x¿afx]ssf tŒjsf k/df0fx' ¿sf aflx/L
;n] ck0" f{ xG' 5g\ . cfkmg\ f aflx/L ;]ndf 8K' n]6 jf cS66] cj:yf k|fKt ug{ oL tŒjsf k/df0f'x¿
/f;folgs kl| tlj|mofdf efu lng] ub5{ g\ .

/f;folgs aG8x¿ w]/} lsl;dsf xG' 5g\ . t/ o; PsfOdf xfdLn] On]S6«fg] EofnG] 6 aG8 jf
cfofl] gs aG8 / sf]EofnG] 6 aG8sf af/d] f dfq cWoog ug]{ 5fF} .

On]S6f« ]EofnG] 6 aG8 (Electrovalent bond)

;fwf/0ftof wfts' f k/df0f'x¿sf] ;ae} Gbf aflx/L ;]ndf 1, 2 jf 3 On]S6f]g /xs] f x'G5g\ . To;
sf/0f tL tŒjsf k/df0fx' ¿n] cfkm\gf] aflx/L ;n] af6 1, 2 jf 3 cf6] f OnS] 6«fg] x¿ u'dfP/ cS6]6
jf 8'Kn6] cj:yf xfl;n ug]{ ub5{ g\ .

To;u} /L cwft' tŒjx¿sf k/df0f'x¿sf] ;ae} Gbf aflx/L ;]ndf 5, 6 jf 7 cf]6f On]S6f« g] x¿
/x]sf xG' 5g\ . To;sf/0f tL tŒjsf k/df0fx' ¿n] cGo k/df0f'sf] aflx/L ;]naf6 3, 2 jf 1

lj1fg tyf kl| jlwM sIff ( 233

OnS] 6«fg] kf| Kt u/L cS6]6 jf 8K' n6] cj:yf k|fKt ug]{ ub{5g\ . wft' / cwft'lar /f;folgs
kl| tlj|mof xF'bf wft'sf k/df0fn' ] cfkmg\ f] aflx/L ;]naf6 Ps jf a9L On]S6f« g] u'dfpFbf of] wgfTds
rfho{ 'St (positively charged) cfof]g aG5 . To;u} /L sg' } cwft'sf k/df0fn' ] cfkmg\ f] aflx/L
;n] df cGo k/df0fa' f6 OnS] 6f« g] x¿ kf| Kt ubf{ of] C0ffTds rfh{oS' t (negatively charged)
cfofg] aG5 . o; jm| ddf tL b'O{ ljk/Lt rfh{o'St cfof]gx¿lar cfsif0{ f an pTkGg x'G5 /
c0fs' f ¿kdf Psfk;df ldn]/ a:5g\ .

o; k|lj|mofdf wft' / cwfts' f k/df0fx' ¿lar aGg] aG8nfO{ OnS] 6«f]Eofn]G6 aG8 elgG5 .
o;/L Wfft'sf k/df0fs' f] EofnG] ; ;]ndf ePsf On]S6f« g] x¿ cwfts' f k/df0f'sf] EofnG] ; ;]ndf
:yfgfGt/0f eO{ aGg] /f;folgs aG8nfO{ OnS] 6f« ]EofnG] 6 aG8 elgG5 .

On]S6«f]EofnG] 6 aG8af6 ag]sf of}lusx¿nfO{ OnS] 6f« ]EofnG] 6 of}lus elgG5 . vfg] g'g jf
;fl] 8od Snf/] fO8 (NaCl), SoflN;od Snf/] fO8 (CaCl2), DofUgl] ;od cS;fO8 (MgO) cflb
ofl} usx¿df OnS] 6f« E] ofnG] 6 aG8 /x]sf] xG' 5 . To;}n] logLx¿nfO{ OnS] 6«f]EofnG] 6 ofl} us elgG5 .

sx] L On]S6«fE] ofnG] 6 ofl} usx¿ aGg] tl/sf

-s_ ;f]l8od Snf/] fO8 (NaCl) aGg] tl/sf

;f]l8od Snf/] fO8 (NaCl) df ;f]l8odsf] Pp6f k/df0f' / Snf]l/gsf] Pp6f k/df0fl' ar
Pp6f OnS] 6f« ]g n]gbg] af6 On]S6f« ]Eofn]G6 aG8 a]g]sf] xG' 5 . ;fl] 8od k/df0f'sf]
On]S6«f]g ljGof; 2, 8, 1 x'G5 . o;sf] ;a}eGbf aflx/L ;n] (valence shell) df Pp6f dfq
OnS] 6f« g] /xs] f] xG' 5 . To;}u/L Snfl] /g k/df0fs' f] On]S6«f]g ljGof; 2, 8, 7 xG' 5 . o; k/
df0f'sf] ;ae} Gbf aflx/L ;]ndf ;ftcf6] f On]S6f« g] x¿ /xs] f xG' 5g\ .

;f]l8od k/df0fn' ] cfkm\gf] Eofn]G; ;]naf6 Pp6f On]S6f« ]g ud' fpbF f wgfTds rfh{oS' t

;fl] 8od cfof]g (Na+) aG5 . Na → Na+ + e–

To;}u/L Snf]l/gn] aflx/L ;]ndf Pp6f On]S6«f]g

kf| Kt u//] C0ffTds rfho{ S' t Snf/] fO8 cfof]g

(Cl–) aG5 . Cl + e– → Cl–

oL b'O{ ljk/Lt rfh{o'St cfof]gx¿lar
cfsif0{ f eO{ On]S6f« E] ofnG] 6 aG8 aGb5 .
h;sf] kmn:j¿k ;fl] 8od / Snfl] /gsf]
;o+ fh] gaf6 ;fl] 8od Snf]/fO8 (NaCl) aGb5 .

Na+ + Cl– → NaCl

o;/L On]S6«fE] ofn]G6 aG8 aGbf bj' } tŒjsf
k/df0f'x¿n] cS66] cj:yf kf| Kt ub{5g\ .

234 lrq 14.8
lj1fg tyf k|ljlwM sIff (

-v_ DofUg]l;od cS;fO8 (MgO) aGg] tl/sf

DofUg]l;od cS;fO8df DofUgl] ;od wft' xf] eg] clS;hg cwft' xf] . DofUgl] ;od
k/df0fs' f] OnS] 6«fg] ljGof; 2, 8, 2 xG' 5 . o;sf] ;a}eGbf aflx/L ;]n (valence shell)
df bO' {cf6] f dfq On]S6«f]g /x]sf xG' 5g\ . To;}u/L clS;hg k/df0fs' f] On]S6f« g] ljGof;
2, 6 x'G5 . o; k/df0fs' f] aflx/L ;]ndf 5cf6] f On]S6f« ]gx¿ /x]sf x'G5g\ . To;sf/0f
DofUgl] ;od k/df0fn' ] EofnG] ; ;]naf6 2 cf]6f OnS] 6«f]gx¿ ud' fP/ wgfTds rfho{ S' t
DofUgl] ;od cfofg] (Mg++) agfpF5 .

Mg → Mg++ + 2e–

o;u} /L clS;hgsf] k/df0f'n] DofUgl] ;odsf] k/df0f'af6 2 cf6] f On]S6«fg] x¿ k|fKt u/L
C0ffTds rfh{oS' t cS;fO8 cfof]g (O– –) agfp5F .

O + 2e– → O– –

oL bO' { ljk/Lt rfho{ 'St cfof]gx¿lar On]S6f« E] ofn]G6 aG8 aGb5 . h;sf] kmn:j¿k
DofUg]l;od cS;fO8sf] lgdf0{ f xG' 5 .

Mg++ + O – – → MgO

-u_ SoflN;od Snf]/fO8 (CaCl2) aGg] tl/sf

SoflN;od Snf]/fO8 (CaCl2) Pp6f
SoflN;od / b'Oc{ f6] f Snfl] /g k/df0fl' ar
OnS] 6f« ]Eofn]G6 aG8af6 aGg] of}lus xf] .
SoflN;od k/df0f'sf] ;ae} Gbf aflx/L ;n] df
b'O{cf]6f OnS] 6«f]gx¿ /x]sf xg' fn] o;n] tL
b'O{ On]S6f« ]gx¿ ud' fP/ wgfTds rfho{ S' t
SoflN;od cfofg] (Ca++) agfp5F .

Ca → Ca++ + 2e–

aG8 aGg] k|lj|mofdf SoflN;odsf] aflx/L ;] lrq 14.9
ndf /x]sf bO' c{ f]6f OnS] 6f« g] x¿dWo] Pp6f On]
S6«fg] Pp6f Snfl] /gsf] k/df0f'sf] aflx/L ;]
ndf :yfgfGt/0f x'G5 eg] csf{] OnS] 6f« ]g bf];|f]
Snf]l/g k/df0f'sf] aflx/L ;n] df :yfgfGt/0f
x'G5 . o;/L bO' {cf6] f Snf/] fO8 cfof]gx¿ aG5g\ .

2Cl + 2e– → 2Cl–

lj1fg tyf k|ljlwM sIff ( 235

oL bO' { ljk/Lt lrq 14.10
rfh{oS' t
cfof]gx¿lar
cfsif{0f eO{ OnS] 6«f]
Eofn]G6 aG8 aGb5
. h;sf] kmn:j¿k
SoflN;od / Snf]
l/gsf] ;+ofh] gaf6
SoflN;od Snf]/fO8
(CaCl2) aG5 .

ljm| ofsnfk 14.4

cfjZos ;fdu|L M Pp6f sf8af]8{ kk] /, dfs/{ , sDkf;, k]lG;n, wfuf,] ud / ljleGg /
ªsf kft] ], s/] fpsf bfgf, df6f]sf anx¿ cflb .

ljlw

cfjZos ;fduL| ;ª\sng ug'x{ f;] \ .

;ªs\ lnt ;fduL| x¿sf] k|ofu] u/L ;fl] 8od, DofUg]l;od, SoflN;od, Snf]l/g / clS;hg
k/df0fs' f 5'6\6f56' 6\ } gdg' f agfpgx' f;] \ .

cjnfs] g / 5nkmn M tof/ ul/Psf gd'gfx¿ ko| f]u u/L OnS] 6f« g] x¿sf] :yfgfGt/0f u/L
;f]l8od Snf]/fO8, SoflN;od Snf/] fO8, DofUgl] ;od Snf/] fO8, DofUg]l;od cS;fO8
cflb aGg] tl/sf sIffdf 5nkmn / k|bzg{ ug{x' f;] \ .

OnS] 6f« E] ofn]G6 ofl} ussf ljzi] ftfx¿ (Characteristics of electrovalent compounds)

OnS] 6«fE] ofnG] 6 ofl} ussf lgDglnlvt ljz]iftfx¿ xG' 5g\ M

-s_ OnS] 6«fE] ofnG] 6 of}lusx¿ wft' / cwftx' ¿ ldn]/ ag]sf x'G5g\ .

-v_ OnS] 6«f]EofnG] 6 ofl} usx¿ kfgLdf 3'ngzLn x'G5g\ . oL ofl} usx¿ kfgLdf 3n' /] wgfTds
/ C0ffTds cfof]gx¿ lbG5g\ .

-u_ oL of}lusx¿sf] pDng] / kUng] laGb' pRr xG' 5 .

sfE] ofn]G6 aG8 (Covalent bond)

xfO8«f]hgafx]s cwft' tŒjx¿sf k/df0f'x¿sf] Eofn]G; ;n] df 5, 6 jf 7 cf6] f OnS] 6«f]gx¿
/xs] f xG' 5g\ . To;sf/0f tL tŒjsf k/df0f'x¿n] cGo k/df0f'af6 3, 2 jf 1 OnS] 6f« ]g kf| Kt
u/L cS6]6 jf 8'Kn]6 cj:yf kf| Kt ug{ vfH] 5g\ . bO' { jf bO' e{ Gbf w/] } cwfts' f k/df0fx' ¿lar
/f;folgs kl| tljm| of xbF' f bj' n} ] OnS] 6f« g] kf| Kt ug{ vfH] g] ePsfn] OnS] 6f« g] sf] ng] bg] ;Dej xbF' g} .

236 lj1fg tyf k|ljlwM sIff (

o:tf] cj:yfdf k/df0fx' ¿lar OnS] 6f« g] ;fem]bf/L u//] cS6]6 jf 8'Kn]6 cj:yfdf k|fKt x'G5 /
/f;folgs aG8 aGb5 . o:tf] /f;folgs aG8nfO{ sf]Eofn]G6 aG8 elgG5 . b'O{ jf b'Oe{ Gbf a9L
;dfg jf c;dfg cwfts' f k/df0fx' ¿lar a/fa/ OnS] 6f« g] hf8] Lsf] ;femb] f/Laf6 aGg] /f;folgs
aG8nfO{ sff]Eofn]G6 aG8 (covalent bond) elgG5 .

sfE] ofn]G6 aG8nfO{ k/df0f'x¿sflar l;wf /]vf ( – ) nufP/ hgfOG5 . cwft'x¿n]
sf]EofnG] 6 of}lus agfpg] jm| ddf Ps hf8] L, bO' { hf8] L jf tLg hf8] L OnS] 6f« ]gx¿ ;femb] f/L ug{
;S5g\ . kfgLsf] c0f' (H2O), xfO8«fS] nfl] /s cDn (HCl), ldy]g (CH4), Pdf]lgof (NH3) cflbdf
sf]Eofn]G6 aG8 kfOG5 . o:tf ofl} usx¿nfO{ sf]Eofn]G6 of}lus elgG5 .

xfO8«fS] nfl] /s cDn (HCl) aGg] tl/sf

Pp6f xfO8f« h] g k/df0f' (H) / Pp6f Snfl] /g k/df0f' (Cl) ldn/] ] xfO8f« ]Snf]l/s cDn (HCl)
sf] Pp6f c0f' aGb5 . oxfF xfO8«f]hg k/df0f'sf] K-shell df hDdf Pp6f OnS] 6«f]g 5 eg]
Snf]l/gsf] Eofn]G; ;]ndf ;ftcf6] f OnS] 6«f]g 5g\ . To;sf/0f xfO8«fh] g / Snf]l/gsf k/df0fn' ] Ps
hf]8L OnS] 6«f]g ;femb] f/L ubf{ xfO8«fh] gn] 8'Kn6] cj:yf k|fKt ub{5 eg] Snf]l/gn] cS6]6 cj:yf
k|fKt ub{5 . o;sf] kmn:j¿k xfO8f« ]Snf]l/s cDnsf] c0f' aGb5 . o;/L sf]Eofn]G6 aG8af6
xfO8f« S] nf]l/s cDn ags] f] xbF' f o;nfO{ sfE] ofnG] 6 ofl} us elgG5 .

H Cl or H - Cl

kfgL (H2O) sf] c0f' aGg] tl/sf

kfgLsf] Pp6f c0f'df b'Oc{ f]6f xfO8«fh] gsf k/df0f' / Pp6f clS;hgsf] k/df0f' x'G5 . xfO8«fh] g
k/df0f'df hDdf Pp6f OnS] 6«fg] x'G5 eg] clS;hgsf] k/df0fd' f sn' cf7cf6] f OnS] 6f« ]gx¿ /x]sf
xG' 5g\ . oL k/df0fx' ¿sf] OnS] 6f« ]g ljGof; o; ks| f/ /xs] f] 5 M

tŒj M clS;hg tŒj M xfO8f« h] g

;]n ;n]

K L K L

2 6 1

lj1fg tyf k|ljlwM sIff ( 237

On]S6f« g] ljGof;sf cfwf/df xfO8«f]hg k/df0f'df hDdf Pp6f On]S6«f]g xG' 5 eg] clS;hg
k/df0fs' f] EofnG] ; ;]ndf 5cf]6f OnS] 6«f]gx¿ /xs] f x'G5g\ . To;sf/0f clS;hgsf] Pp6f
k/df0f'n] xfO8f« h] gsf b'O{cf]6f k/df0f';Fu Ps Ps hf8] L On]S6«fg] ;femb] f/L ubf{ xfO8f« h] g
k/df0fx' ¿n] 8'Kn6] cj:yf k|fKt ub5{ g\ eg] clS;hg k/df0fn' ] cS6]6 cj:yf kf| Kt ub5{ . o;/L
kfgLsf] c0fd' f xfO8f« ]hg / clS;hglar sfE] ofnG] 6 aG8 aG5 . sfE] ofnG] 6 aG8af6 aGg] ePsfn]
kfgLnfO{ sfE] ofn]G6 of}lus elgG5 .

H O H or H - O - H

ldy]g (CH4) aGg] tl/sf
Pp6f sfa{g k/df0f' / rf/cf]6f xfO8f« h] g k/df0fx' ¿lar rf/hf8] L OnS] 6f« g] x¿sf]
;femb] f/Laf6 ldy]gsf] c0f' aG5 . xfO8f« h] g k/df0fs' f] K- ;]ndf Pp6f dfq On]S6f« ]g xG' 5 eg]
sfag{ k/df0f'sf] Eofn]G; ;]ndf rf/cf]6f OnS] 6«f]gx¿ xG' 5g\ . To;sf/0f Pp6f sfag{ k/df0fn' ]
rf/cf6] f xfO8«f]hg k/df0f;' Fu rf/hf8] L OnS] 6f« ]g ;femb] f/L u/]/ cS66] cj:yf kf| Kt ub{5 eg]
;fx] L j|mddf xfO8f« ]hg k/df0fx' ¿n] 8'Kn]6 cj:yf k|fKt ub5{ g\ . o;sf] kmn:j¿k ldyg] (CH4)
c0f'sf] lgdf0{ f xG' 5 . ldyg] c0fd' f sfag{ / xfO8f« h] g k/df0fx' ¿lar sfE] ofnG] 6 aG8 /xs] f] x'gfn]
o;nfO{ sf]Eofn]G6 ofl} us elgG5 .

238 lj1fg tyf k|ljlwM sIff (

Pdf]lgof (NH3) aGg] tl/sf
gfO6«fh] gsf] Pp6f k/df0f' / xfO8«f]hgsf tLgcf6] f k/df0f'x¿lar tLg hf8] L On]S6f« g] sf]
;fem]bf/Laf6 Pdfl] gof (ammonia) sf] c0f' aGb5 .
gfO6«f]hg k/df0fs' f] EofnG] ; ;n] df kfFrcf6] f OnS] 6«fg] /xs] f x'G5g\ . aflx/af6 tLgcf6] f
OnS] 6«f]g kf| Kt u/L o;n] cS66] cj:yf k|fKt u5{ . To;} u/L xfO8«fh] gsf] k/df0f'df hDdf
Pp6f dfq On]S6«fg] /x]sf] x'G5 . To;sf/0f gfO6f« ]hgsf] Pp6f k/df0f'n] xfO8«fh] gsf tLgcf]6f
k/df0f;' uF Ps Ps hf]8L On]S6f« ]gsf] ;femb] f/L ubf{ gfO6f« h] gn] cS66] cj:yf k|fKt ub{5
eg] tLgcf6] } xfO8«fh] g k/df0fx' ¿n] 8'Kn]6 cj:yf k|fKt ub5{ g\ . h;sf] kmn:j¿k Pdfl] gof
c0f' (NH3) sf] lgdf0{ f xG' 5 . Pdfl] gof c0fd' f sf]Eofn]G6 aG8 /xs] f] x'gfn] o;nfO{ sfE] ofn]G6
of}lus elgG5 .

lrq

lj|mofsnfk 14.5

cfjZos ;fdu|L Msf8a{ f8] { k]k/, ljleGg /ªsf kf]t,] s]/fpsf bfgf, df6fsf ;;fgf anx¿,
dfs/{ , sDkf;, k]lG;n, ud tyf wfuf] cflb .

ljlw

cfjZos ;fdu|L ;ªs\ ng ug{x' f;] \ .

;ª\slnt ;fdu|Lx¿sf] k|ofu] u/L xfO8«fh] g, sfa{g, gfO6f« ]hg / clS;hg
k/df0fs' f df8] nx¿ agfpg'xf];\ .

tof/ ul/Psf gd'gfx¿ k|ofu] u/L kfgL, ldyg] , Pdfl] gof / xfO8«fS] nf]l/s Pl;8sf c0fd' f
sf]EofnG] 6 aG8 aGbf xg' ] OnS] 6f« g] hf]8fsf] ;fem]bf/Lsf tl/sf k|bz{g ug'{xf];\ .

cjnfs] g / 5nkmn M tof/ ul/Psf gdg' fx¿ kb| z{g u/L OnS] 6f« ]gx¿sf] ;femb] f/Laf6 aGg]
kfgL, ldy]g, Pdf]lgof / xfO8«f]Snfl] /s Pl;8sf gdg' fx¿ dfly sIffdf 5nkmn ug{x' f;] \ .

sfE] ofn]G6 ofl} ussf ljz]iftfx¿ (Characteristics of covalent compounds)

sf]Eofn]G6 ofl} ussf lgDglnlvt ljz]iftfx¿ x'G5g\ M

-s_ sf]Eofn]G6 ofl} usx¿ Ps jf PseGbf w/] } cwftx' ¿ ldn/] ags] f x'G5g\ .

lj1fg tyf kl| jlwM sIff ( 239

-v_ kf| oh;f] sfE] ofn]G6 ofl} usx¿ kfgLdf 3'ngzLn xb' }gg\ .

-u_ sf]Eofn]G6 of}lusx¿af6 wgfTds / C0ffTds cfofg] x¿ kf| Kt xbF' g} g\ .

-3_ oL of}lusx¿sf] pDng] / kUng] laGb' Gog" x'G5 .

cf0fljs ;"q (Molecular formula)

of}lussf] ;a}eGbf ;fgf] c+znfO{ c0f' (molecule) elgG5 . c0f' bO' { jf b'Oe{ Gbf a9L
k/df0f'x¿sf] /f;folgs ;o+ f]hgaf6 aGb5, h:tM} kfgLsf] c0f' (H2O) xfO8f« h] gsf b'O{cf6] f
k/df0f' / clS;hgsf] Pp6f k/df0f' ldn/] ag]sf] x'G5 . To;}u/L ;f]l8od Snf/] fO8 (NaCl) sf]
c0f' ;f]l8od (Na) / Snf]l/g (Cl) sf k/df0fx' ¿sf] ;o+ fh] gaf6 ags] f] x'G5 . xfO8«fh] g (H2)
sf] c0f' b'Oc{ f6] f xfO8«f]hg (H) sf k/df0fx' ¿ ldn]/ ag]sf] xG' 5 . To;}u/L clS;hgsf] c0f\' (O2)
b'O{cf6] f clS;hgsf k/df0f' (O) x¿ ldn/] ags] f] x'G5 . tŒjsf] ;ª\st] h:t} c0f'x¿nfO{ klg
5f6] s/Ldf n]Vbf ;ªs\ ]t jf ;ªs\ t] ;dx" sf] k|of]u ul/G5 . o;nfO{ cf0fljs ;"q (Molecular
formula) elgG5 . To;sf/0f sg' } c0fn' fO{ hgfpg] k/df0f'x¿sf] ;ªs\ t] ;dx" nfO{ g} cf0fljs
;"q elgG5 . pbfx/0fsf nflu sx] L c0f' / ltgLx¿sf cf0fljs ;q" tnsf] tflnsfdf lbOPsf] 5 M

j|m=;= c0fx' ¿sf] gfd cf0fljs ;"q
1. xfO8«fS] nf]l/s cDn
2. ;Nkml/s Pl;8 HCl
3. ;f]l8od xfO8«fS] ;fO8
4. DofUg]l;od xfO8«fS] ;fO8 H2SO4
5. Pdfl] gof NaOH
6. ;fl] 8od Snf/] fO8
7. DofUg]l;od sfafg]{ 6] Mg(OH)2
8. DofUg]l;od Snf/] fO8 NH3
9. kfgL NaCl
10. SnflN;od sfafg{] ]6
11. sfag{ 8fOcS;fO8 MgCO3
12. Kff]6fl;od gfO6]«6 MgCl2
13. ;fl] 8od afOsfaf{g] 6] H2O
14. SoflN;od sfaf{]g6] CaCO3
15. Kff]6fl;od ;Nkm6] CO2
16. Pdfl] god km:km6] KNO3
NaHCO3
CaCO3
K2SO4
(NH4)3PO4

240 lj1fg tyf kl| jlwM sIff (

cf0fljs ;q" n]Vg] tl/sf (Method of writing molecular formula)

lj|m;jm| ; ljlw (criss-cross method) sf] k|ofu] u/L xfdL ljleGg ks| f/sf of}lusx¿sf] cf0fljs
;q" nV] g] u5f{}F . o; ljlwaf6 cf0fljs ;q" nV] g] tl/sf tn lbOPsf] 5 M

1. ;jk{ |yd hg' c0f'sf] cf0fljs ;q" nV] g'kg{] xf] To;sf] gfd nV] g'kg{] xG' 5 .

Hf:t} M DofUg]l;od Snf]/fO8

2. pSt c0f' sg' s'g tŒjsf k/df0fx' ¿ jf cfofg] x¿ ldn/] ags] f] 5 tL k/df0f'x¿sf]
;ª\st] c0f'sf] gfdsf] l7s tn n]Vg'k5{ .

h:t} M DofUgl] ;od Snf]/fO8

Mg Cl

3. ;ªs\ t] sf] l7s dfly ;DalGwt k/df0f' jf cfofg] sf] ;o+ H' otf nV] gk' 5{ .

Hf:t} M DofUgl] ;od Snf]/fO8

2 1

Mg Cl

4. To;kl5 k/df0f' jf cfofg] lar ;+o'Hotf ;f6f;f6 ugk{' b5{ . o; s'/fnfO{ jf0f lrx\g (→)
n] hgfpgk' b{5, h:tM}

DofUgl] ;od Snf]/fO8

2 1

Mg Cl

5. To;kl5 tŒjsf] k/df0f' jf cfofg] lag ;+oH' otf ;f6f;f6 u/L ;ªs\ t] / To;sf] dl' g
;+oH' otf n]Vg'kb{5, h:t} M

DofUgl] ;od Snf]/fO8

2 1

Mg Cl

Mg1Cl2

t/ sg' } tŒj jf cfofg] sf] ;+oH' otf 1 eP To;nfO{ nV] g' kbg{} . To;} u/L bj' } ;o+ 'Hotfx¿nfO{

s'g} ;ªV\ ofn] efu hfG5 eg] efu nfUg] u/L x6fP/ afsF L ;ªV\ of /fv]/ cf0fljs ;"q
nV] g'kb{5 . To;}u/L cfofg] PseGbf a9L tŒjsf] k/df0f'af6 ag]sf] 5 eg] cfofg] sf]

;ª\s]t ;dx" nfO{ sfi] 7 ( ) leq /fVg'kb{5 / sfi] 7sf] aflx/ dl' g bfofFlt/ ;+o'Hotf

nV] g'kb{5, h:t} M

lj1fg tyf kl| jlwM sIff ( 241

;fl] 8od Snf/] fO8 DofUgl] ;od afOsfaf{]g]6

1 1 2 1

Na Cl Mg HCO3

Na1Cl1 Mg1 (HCO3)2

= NaCl = Mg(HCO3)2

sx] L of}lusx¿sf cf0fljs ;"q tn lbOPsf] 5 M

cf0fljs ;q" af6 yfxf kfpg ;lsg] tYox¿ M
1. c0fd' f /xs] f tŒjx¿sf] gfd / ;ªs\ ]t
2. tŒj jf cfofg] sf] ;+oH' otf
3. c0fd' f /x]sf k/df0f'x¿sf] ;ªV\ of

kf/df0fljs ef/ / cf0fljs ef/ (Atomic weight and Molecular weight)

s'g} k/df0fs' f] Go'lSno;df /xs] f kf| ]6f]g / Go'6f« g] sf] ;ªV\ ofsf] of]ukmnnfO{ pSt k/df0fs' f]
kf/df0fljs ef/ (atomic weight) elgG5 .

kf/df0fljs ef/ Ö k|f6] f]gsf] ;ª\Vof ± Go'6«f]gsf] ;ªV\ of

242 lj1fg tyf k|ljlwM sIff (

s]xL k/df0fx' ¿sf] Kf/df0fljs ef/ (Atomic weight of some atoms)

clS;hgsf] k/df0f' (O) sf] Gol' Sno;df 8 cf6] f kf| ]6fg] / 8 cf]6f Go'6f« g] x¿ /xs] f xG' 5g\ .

clS;hgsf] k/df0f' ef/ = p+ + no

= 8 + 8
= 16

ctM clS;hgsf] k/df0fljs ef/ (8 + 8) = 16 xG' 5 .

;fl] 8od k/df0f'sf] Gol' Sno;df 11 cf6] f k|f]6f]g / 12 cf6] f Go6' «f]g /xs] f xG' 5g\ . To;sf/0f
;f]l8od (Na) k/df0fs' f] kf/df0fljs ef/ (11+12) = 23 xG' 5 .

cf0fljs ef/ (Molecular Weight)

sg' } klg c0fd' f ePsf ;a} k/df0fx' ¿sf] kf/df0fljs ef/sf] ofu] kmnnfO{ g} pSt c0f'sf]
cf0fljs ef/ (molecular weight) elgG5 . c0fd' f ePsf k/df0fx' ¿sf] kf/dfl0fs ef/ hf8] ]/
cf0fljs ef/ kQf nufOG5, h:t} M

1. kfgL (H2O) sf] cf0fljs ef/ = 2 × H + 1 × O

= 2 × 1 + 1 × 16

= 2 + 16

= 18

2. Pdf]lgod km:km6] (NH4)3PO4 sf] cf0fljs ef/ = 3 × N + 12 × H + 1 × P + 4 × O
= 3 × 14 + 12×1+1×15+4×16


= 42 + 12 + 15 + 64

= 133

/l] 8of]wdL{ tŒj (Radioactive Elements)

kf/df0fljs ;ªV\ of w/] } ePsf sx] L k/df0f'sf Go'lSno;x¿ cl:y/ x'G5g\ . oL cl:y/
k/df0f'x¿n] l:y/tf k|fKt ug{sf nflu PsfPs cNkmf (α), la6f (β) / ufdf (γ) gfdsf
zlStzfnL ljls/0fx¿ pT;h{g ub{5g\ . o; k|sf/sf tTjx¿nfO{ /]l8ofw] dL{ tTj elgG5 . ctM
/l] 8of]wdL{ ljls/0f pT;h{g ug{ ;Sg] tTjx¿nfO{ /l] 8of]wdL{ tTj elgG5 . o'/]lgod, Kn'6fl] god,
yfl] /od cflb /]l8of]wdL{ tTjsf pbfx/0f x'g\ . kf| oM h;f] /l] 8of]wdL{ tTjsf] kf/df0fljs ;+Vof
80 eGbf a9L xG' 5g .

lj1fg tyf kl| jlwM sIff ( 243

/l] 8of]wdL{ pT;h{g (Radioactive Emission)

/l] 8ofw] dL{ tŒjx¿af6 cNkmf (α), la6f (β) / ufdf (γ) gfdsf zlStzfnL ljls/0fx¿ pT;hg{
ug]{ kl| jm| ofnfO{ /]l8of]wdL{ pT;h{g (radioactive emission) elgG5 . /]l8ofw] dL{ pT;hg{ af6
pTkGg xg' ] ljls/0fx¿ dfgj :jf:Yosf nflu cToGt} xflgsf/s x'G5g\ . /]l8of]wdL{ ;ljm| otf
tyf /]l8ofw] ldt{ f (Rdioactivity) sf] vf]h ;g\ 1896 df k|mfG;sf j}1flgs xg] /L a]s/]n (Henri
Becquerel) n] uge'{ Psf] xf] .

k/df0fx' ¿df b'O{ lsl;dsf /l] 8ofw] dL{ ;ljm| otf xg' ] ub5{ g\ . tL x'g\ Go'lSno/ lkm;g / Go'lSno/
ˆoh' g . Go'lSno/ lkm;g / Gol' Sno/ ˆo'hgnfO{ ;dud| f GolSno/ k|ltlj|mof elgG5 .

Gol' Sno/ lkm;g (Nuclear fission)

kf/df0fljs ;ª\Vof w]/} ePsf tŒjx¿sf] cl:y/ k/df0f' 6l' j|mP/ ;fgf k/df0fx' ¿ aGg] k|lj|mofnfO{
Gol' Sno/ lkm;g elgG5 . o; kl| jm| ofdf /]l8ofw] dL{ tŒjx¿ h:t}M o/' ]lgod, Kn'6f]lgod cflbsf
k/df0fx' ¿nfO{ tLj| ultsf] :jtGq Go'6«f]gn] lxsf{pFbf tL k/df0f' 6'lj|mg uO{ ;fgf ;fgf gofF
tŒjsf k/df0f'x¿ pTkGg x'G5g\ . o;/L cl:y/ k/df0f'af6 l:y/ k/df0f'sf] lgdf0{ f x'g] jm| ddf
s]xL lk08 gfz x'G5 . gfz ePsf] lk08af6 cNkmf (α), la6f (β) jf ufdf (γ) sf ¿kdf ckf/
pmhf{ pTkfbg x'G5 .

pbfx/0fsf nflu o'/]lgod k/df0f'nfO{ pRr ultsf] Go6' f« g] n] lxsf{pbF f pSt k/df0f' ljR5]bg xg'
uO{ al] /od / lj|mK6g gfds xns' f k/df0fs' f ;fy} tLgcf]6f Go'6«f]gx¿ / gfz ePsf] lk08af6
ckf/ pmhf{ pTkGg xG' 5 .

o'/]lgod ± Go'6«f]g a]l/od ± lj|mK6g ± Go'6f« g] ± pmhf{ -ljls/0fsf ¿kdf_

Gol' Sno/ km\oh' g (Nuclear fusion)

cTolws dfqfdf tfk / rfksf] pkl:yltdf xfO8«fh] g h:tf xn'sf tŒjsf k/df0f'x¿
;o+ fh] g eO{ 7n' f] tŒj -h:tM} lxlnod_ / pmhf{ lgdf0{ f xg' ] kl| jm| ofnfO{ Gol' Sno/ ˆoh' g elgG5 .
of] k|ljm| of ;"o{ / tf/fx¿df lg/Gt/ eO/xs] f] x'G5 . ;o" { tyf tf/fx¿df kz| :t dfqfdf x'g]
xfO8«fh] g / clt pRr tfk / rfkn] ubf{ Go'lSno/ kmo\ 'hg ;Dej ePsf] xf] . o; kl| tljm| ofdf
rf/cf6] f xfO8f« h] g k/df0fx' ¿sf] ;o+ fh] g eO{ Pp6f lxlnodsf] k/df0f' / ckf/ pmhf{ pTkfbg xG' 5

xfO8f« ]hg lxlnod ± pmhf{

k/df0f' pmhf{ jf Gol' Sno/ pmhf{ (Atomic energy or Nuclear energy)

Go'lSno/ k|ltlj|mofaf6 pTkGg x'g] pmhfn{ fO{ k/df0f' pmhf{ jf Gol' Sno/ pmhf{ elgG5 . sl[ td
tl/sfn] Gol' Sno/ lkm;g kl| tlj|mofaf6 phf{ pTkfbg ug{ ;lsG5 . Gol' Sno/ ˆo'hg kl| tlj|mofsf
nflu cTolws tfk / rfksf] cfjZostf kg{] ePsfn] s[ltd ¿kdf of] k|lj|mofaf6 phf{
lgsfNg ;lsFb}g . Go'lSno/ kl| tlj|mofaf6 tfk zlSt pTkfbg ug{ cf0fljs e66\ Lx¿ agfOPsf
x'G5g\ . e66\ Laf6 pTkflbt tfk zlStn] kfgL pdfn/] afkm agfO{ ;f] afkmaf6 jfik OlGhg

244 lj1fg tyf k|ljlwM sIff (

rnfOG5 . pSt jfik OlGhgn] hg] /] ]6/ ;~rfng u/L kr| /' dfqfdf ljB't\ pTkfbg ug{
;lsG5 . o; kl| jlwaf6 kf| oMh;f] ljsl;t /fi6«x¿df ljB't\ pTkfbg ug]{ ul/G5 .

To;u} /L Gol' Sno/ kl| tljm| ofaf6 k|fKt ljls/0fsf] k|of]u u/L vfgk] fgL, vfB kbfy,{ dl] 8sn
cfh} f/ cflbnfO{ lgdn{ Ls/0f ug;{ dt] k/df0f' pmhf{sf] pkof]u ul/G5 . k/df0f' pmhf{nfO{ SofG;/
h:tf ljleGg k|sf/sf /fu] x¿sf] pkrf/ ug{ klg pkofu] ul/G5 . o;sf ;fy;fy} Go'lSno/
pmhf{sf] k|of]uaf6 aGg] cf0fljs xftxltof/sf] b?' kofu] tyf Go'lSno/ pmhf{ pTkfbg ubf{ r'lxg]
ljls/0fx¿n] dfgj hfltsf nflu 7'nf] hfl] vd klg plQs} /x]sf] 5 .

kl/of]hgf sfo{

k/df0f' pmhf{sf pkof]u / xflgsf/s c;/x¿af/] k:' ts, kqklqsf tyf OG6/g]6df vfh] L
ug{'xf;] \ .

vfh] ul/Psf hfgsf/Lx¿nfO{ snfTds tl/sfn] rf6{kk] /df n]vL sIffdf k:| t't ug'{xf];\
/ 5nkmn ug{x' f];\ .

5nkmnsf cfwf/df æk/df0f' pmhf{ lj1fgsf] a/bfg ls cle;fkÆ eGg] lJifodf sIffdf jfbljjfb
kl| tof]lutf cfof]hgf ugx{' f;] \ .

5nkmn / jfbljjfbaf6 l;s]sf s'/fx¿ ;d]6L ægk] fndf Go'lSno/ phf{Æ ljifodf 5f]6f]
kl| tjb] g tof/ ugx'{ f;] \ .

cEof; 245

!= ldNg] pQ/df l7s lrx\g -√_ nufpg'xf];\ M
-s_ tTjnfO{ 6j' m| ofpFbf k|fKt x'g] ;a}eGbf ;fgf] c+znfO{ s] elgG5 <
-c_ c0f' -cf_ k/df0f'
-O_ Gol' Sno; -O_ kf| 6] f]g
-v_ kf/df0fs' f] cfi} ft Jof; slt x'G5 <
-c_ 10-10 m -cf_ 1010 m
-O_ 100 m -O_{ 1000 m
-u_ tn lbOPsf dWo] /l] 8of]wdL{ tŒj sg' xf] <
-c_ o/' l] god -cf_ Kn'6fl] god
-O_ yfl] /od -O_ dflysf ;a}

lj1fg tyf k|ljlwM sIff (

-3_ tn lbOPsf dWo] sg' ofl} usdf sfE] ofnG] 6 aG8 x'G5 <

-c_ NaCl -cf_ H2O
-O_ CaCl2 -O_ MgO
-ª_ tnsf dWo] ;+o'Hotf tLg ePsf] k/df0f' s'g xf] <

-c_ clS;hg -cf_ cfndf]lgod

-O_ SoflN;od -O_ Snf]l/g

-r_ DofUg]l;od afOsfaf{g] ]6sf] cf0fljs ;"q sg' xf] <

-c_ MgCO3 -cf_ Mg(HCO3)2

-O_ MgHCO3 -O_ Mg(CO3)2

@= vfnL 7fp“df pko'St pQ/ eg'x{ f];\ M

-s_ k/df0fs' f] x/s] ;n] jf sIfdf lglZrt pmhf{ x'G5 .

of] tYo kQf nufpg] j1} flgs =============== x'g\ .

-v_ kf/df0fljs ;ª\Vof w]/} ePsf tŒjx¿sf] cl:y/ Go'lSn; 6'ljm| P/ ;fgf k/df0f' aGg]
k|lj|mofnfO{ ==============elgG5 .

-u_ SoflN;odsf] k/df0f'n] cS6]6 cj:yf k|fKt ug{ Eofn]G; ;n] af6 ==============cf6] f
On]S6«fg] x¿ ================kg{] x'G5 .

-3_ Pdf]lgofsf] k/df0f'df =============aG8 x'G5 .

-ª_ SoflN;od Snf/] fO8sf] cf0fljs ;q" ==================xG' 5 .

-r_ ;fl] 8od afOsfaf]{g6] sf] cf0fljs ef/ ============= xG' 5 .

#= km/s nV] g'xf;] \ M

-s_ 8K' n6] / cS6]6

-v_ On]S6«fE] ofn]G6 aG8 / sfE] ofnG] 6 aG8

$= sf/0f lbgx' f;] \ M

-s_ k/df0f' pmhf{ nfebfos / xflgsf/ bj' } xG' 5 .

246 lj1fg tyf k|ljlwM sIff (