शिक्षक निर्देशिका कक्षा ८

PsfO 6 tfk (Heat)

cgd' flgt 3G6L 5 -;}4flGts 4+ ko| f]ufTds 1_

1. l;sfO pknlAw

x Tffk / tfkj|mdsf] kl/ro lbO{ ;DaGw bv] fpg

x Tffkjm| dsf PsfOx¿ -;l] N;o;, km/]gxfO6_ lgwf{/0f ug{] ljlw atfpg / tL
PsfOx¿larsf] cGt/ bv] fO{ ¿kfGt/0f ug{

x ;fwf/0f / lSnlgsn tfkj|md dfks oGq (thermometer) sf] agf]6 / sfo{

k0| ffnL JofVof ug{
2. ljifoj:t' ljefhg / l;sfO ;fdu|L

lbg ljifoj:t' l;sfO ;fdu|L

1 Tffk / tfkj|mdsf] kl/ro, ;DaGw lunf;, lr;fk] fgL, tftfk] fgL, ydf{l] d6/
tyf leGgtf

2 Tfkjm| ddfks oGqsf] agfj6 / To;df ydfl{] d6/ -2 cf6] f M kf/f] / cNsfx] n
/flvg] t/n kbfy{x¿ ko| fu] ul/Psf]_

3 Tffkj|md dfkgoGqdf :s]n lgwf/{ 0f /fp08 a6d ˆnf:s /a/ ss{
-k|ofu] fTds sfo{_ ydfl]{ d6/, L cfsf/df sfrF sf] gnL,

l:k|6 NofDk, ;fn] L, a/km, :6\ofG8,
ljs/

4 tfkjm| dsf PsfOx¿sf] ¿kfGt/0f Tffkj|mdsf] PsfO ¿kfGt/0fsf] rf6{

5 tfkjm| ddfks oGqsf lsl;dx¿ lSnlgsn ydf{]ld6/, ;fwf/0f ydfl]{ d6/

3. ljlzi6 p2]Zo, l;sfO ;xhLs/0f ljm| ofsnfk / d"Nofªs\ g

lbg 1 tfk / tfkjm| dsf] kl/ro, leGgtf / ;DaGw
-s_ ljlzi6 p2]Zo

x Tffksf] kj| fxsf] cjwf/0ff k|i6\ofpg
x Tffk / tfkjm| dsf] kl/ro lbg
x Tffk / tfkjm| dlarsf] ;DaGw tyf leGgtf atfpg
-v_ l;sfO ;xhLs/0f ljm| ofsnfk
lj|mofsnfk 1 M tfksf] kj| fx

49

x ljBfyL{x¿nfO{ bl} gs hLjgdf ePsf tftf] / lr;f] ;DaGwL cg'ejx¿ ;g' fpg
nufO{ 5nkmn u/fpg'xf;] \ / lzIfsn] cfˆgf] cg'ej klg atfpg'xf];\ .

x xfdLn] a/km 5fP] df lr;f] / ttfPsf] kfgL 5fP] df tftf] cge' j ub{5f+F} . lr;f]
jf tftf] cge' j ugfs{ f] sf/0f s] xf]nf < egL 5nkmn u/fpgx' f;] \ /
ljBfyL{x¿nfO{ o:tf] cge' j x'gfsf sf/0f ;f]Wg'xf];\ .

x pgLx¿af6 pTt/ kf| t ePkl5 tfkzlStsf] k|jfxaf/] JofVof ub}{ yk :ki6
kfl/lbg'xf];\ .

:ki6tf M lr;f] jf tftf] cg'ej x'g'sf] d'Vo sf/0f eg]s} tfk zlSt Pp6f j:ta' f6
csf{] j:t'df ;g{' xf] . tfksf] kj| fx hlxn] klg pRr tfkjm| daf6 lgDg tfkjm| dlt/
xG' 5 .
lj|mofsnfk 2 tfk / tfkjm| dsf] kl/ro, ;DaGw / leGgtf
x kf7o\ k':tssf] lj|mofsnfk 1 sIffdf k|bzg{ u/L 5nkmn u/fpgx' f;] \ / k|fKt

lgisifn{ fO{ JofVof ug{x' f;] \ .
x o;sf nflu bO' { cf]6f lunf;dWo] Pp6fdf tftf] / csf]{df lr;fk] fgL /fVg /

bj' }sf] tfkj|md gf]6 ug{ nufpg'xf;] \ .
x To;kl5 7'nf] ef8F fdf b'j} lunf;sf] kfgL ld;fpg nufO{ tfkjm| d gfKg

eGg'xf;] \
ld>0fsf] tfkjm| d lr;fk] fgLsf] eGbf a9L / tftfk] fgLsf] eGbf sd xG' 5 . o;
lj|mofsnfkjf6 lgDg lgisif{ atfpg'xf;] \ .
lgisif{ M tftfk] fgLn] tfk ud' fp5F / lr;f]kfgLn] tfk lnG5 . tfk hlxn] klg
tfkjm| d a9L ePsf] j:ta' f6 tfkjm| d sd ePsf] j:t'lt/ ;b5{ .
x Tfnsf kZ| gx¿df lh1f;f pTkGg u/fO{ k|Tos] kZ| gsf] pTt/ ;fr] ]/ cf cfkm\gf]
skLdf n]Vg nufpg'xf];\ .

Jf:t'nfO{ ttfpFbf tftf]kgf a9\5 jf 365\ < lsg <
Jf:t'nfO{ lr:ofpFbf tfkjm| d 36\5, lsg <
Tffk / tfkjm| ddWo] s'g sf/0f / s'g rflxF c;/ xf] <
Tffkjm| d egs] f] s] xf] <
Tffk egs] f] s] xf] <
Tffk s'g sg' s/' fx¿df e/ k5{g\ <
Tffkjm| d sg' sg' s/' fx¿df e/ k5{ <
Tffk / tfkj|mdnfO{ s'g PsfOdf gflkG5 <
x cGtdf ljBfyL{x¿n] n]v]sf pTt/x¿ k:| tt' ug{ nufpg'xf;] \ / tnsf]
tflnsf rf6{ b]vfO{ pTt/x¿sf] t'ngf ug{ nufpgx' f];\ .

50

tfk / tfkj|mdlarsf] leGgtf

Basis for comparision Heat Temperature
Meaning Heat is the amount of energy in a Temperature is the measure
body. of the intensity of heat
Measures Total kinetic and potential energy Everage kinetic energy of a
contained by molecules in an molecules in a substance.
Property object
Flows from hotter object to cooler Rises when heated and falls
Unit of measurement object. when cooled.
Device Joules Kelvin
Labelled as Calorimeter Thermometer
Q T

-u_ dN" ofª\sg
lgDg kZ| gx¿ ;f]w]/ d"Nofª\sg ug{'xf;] \ M

x tfk s;/L kj| fx x'G5 <
x tfk / tfkjm| dsf] kl/efiff lbg'xf];\ .
x tfk / tfkjm| dlarsf] ;DaGw nV] g'xf;] \ .
x tfk / tfkj|mddf km/s 5'6o\ fpg'xf];\ .
x tfk / tfkj|md sd] f e/ k5g\{ <
-3_ kl/of]hgf sfo{
Pp6f Knfl:6ssf] laF8 ePsf] rSs' lng nufpgx' f];\ . To;sf] wfts' f] efudf kg]{ u/L
rf/ 7fpFdf d}gsf] yfk] f rx' fpg eGgx' f];\ . k|To]s :yfgdf Ps Ps lkg uf8g\
nufpgx' f];\ . rSss' f] 6'Kkfn] fO{ aln/xs] f] d}gaTtLsf] ;xfotfn] ttfpg eGg'xf];\ . ca
s] x'G5 < xg] { nufpg'xf];\ .

lkgx¿df klxn] rSss' f] 6K' kfl] t/df /x]sf / To;kl5 j|mdzM 5p] lt/ /x]sf lkgx¿
9Nb} hfG5g\ . o;af6 s] l;Sg ;lsG5 < ljBfyL{nfO{ lgisif{ n]Vg nufpgx' f;] \ .

-ª_ k|fljlws zAbfjnL

Thermal Equillibrium = tftf] / lr;f] ldl;O{ ;sk] l5sf] ;Gt'lnt cj:yf

ydfl]{ d6/ M tfkj|md gfKg] pks/0f

¿kfGt/0fM Pp6f OsfOaf6 csf{d] f abNg] sfd

-r_ lzIfssf nflu yk ljifoj:t'

ha sg' } 7f;] j:tn' fO{ ttfOG5, To;sf c0f'x¿sf] sDkg a9\g hfG5 / ltgLx¿larsf]
b'/L a9\g hfG5 . kmn:j¿k Intermolecular force 36g\ hfG5 . clg To;leq
c0fx' ¿sf] rnfodfg x'G5g\ / 7f;] j:t' t/ndf kl/0ft xG' 5 .

51

ha s'g} t/n j:tn' fO{ ttfOG5, To;sf c0f'x¿sf] sDkg cem a9\g hfG5 / ltgLx¿
larsf] Force olt 36\5 ls c0fx' ¿ To; j:t' aflx/ efUg yfN5g\ . kmn:j¿k t/n
kbfy{ Uof;F df kl/0ft x'G5 .

olb Uof;F / t/nnfO{ lr:ofpbF } hfg] xf] eg] dflysf] l7s pN6f] kl| j|mof ;'? xG' 5 .
UofF; kbfy{ t/ndf kl/0ft x'G5 eg] t/n kbfy{ 7f];df kl/0ft xG' 5 .

lbg M 2 tfkj|mddfks oGq agfj6 / o;df /flvg] t/n kbfyx{ ¿

-s_ ljlzi6 p2]Zo
x tfkjm| ddfks oGqsf] kl/efiff / l;4fGt atfpg
x ydf]{ld6/sf] agfj6 JofVof ug{
x tfkj|mddfks oGqdf /flvg] t/n kbfy{x¿sf] gfd / ljz]iftf atfpg

-v_ l;sfO ;xhLs/0f lj|mofsnfk
ljm| ofsnfk 1 tfkj|mddfks oGqsf] jgfj6 / l;4fGt

x ljBfyL{x¿nfO{ cfjZostfcg;' f/ ;dx" df ljefhg ug{x' f];\ / kT| o]s ;dx" nfO{
Ps Ps cf6] f ;fwf/0f tfkjm| ddfks oGq ljt/0f ug'{xf];\ .

x k|Tos] ;d"xnfO{ lgDg lnlvt k|Zgdf 5nkmn ug{ nufO{ ;f/fz+ tof/ kf/L
k:| t't ug{ nufpgx' f];\ .
;fwf/0f ydf]l{ d6/ s'g s'g j:tn] ags] f] 5 <
;fwf/0f ydfl{] d6/sf] agf6] s:tf] 5 <
;fwf/0f ydfl{] d6/df aNa eg]sf] s] xf] <
aNadf sg' kbfy{ /flvPsf] x'G5 <
pSt kbfys{ f] u'0fx¿ s] s] xf]nfg\ <
tfkjm| d dfks oGqn] s;/L sfd u5{ <
tfkj|mdsf] dfg s;/L lgsflnG5 <
tfkj|mddfks oGq s'g l;4fGtdf cfwfl/t eO{ sfd u5{ <
;fwf/0f tfkjm| d dfkg oGqdf clxn] slt tfkj|md /x]sf] 5 <
;fwf/0f tfkj|mddfkg oGqsf] ;kmf lrq agfpgx' f];\ .

x Pp6f ;d"xn] k|:tt' ubf{ cGo ;d"xnfO{ cfjZos k[i7kf]if0f lbg nufpg'xf;] \
/ yk ;e' mfj lbgx' f];\ .

lj|mofsnfk 2 tfkjm| ddfks oGqdf /flvg] t/n kbfy{x¿
x lj|mofsnfk Psdf lgdf0{ f ul/Psf] ;d"xdf kf/f] / cNsfx] n ljt/0f u/L bj' }
kbfys{ f] cjnf]sgsf] cfwf/df -kf/fn] fO{ 5'g glbg_] 5nkmn ug{ nufO{
ljzi] ftfx¿sf] ;r" L tof/ ug{ nufpgx' f];\ .

52

x 5nkmn ubf{ kbf{sf] cj:yf, 6NsfO, plDng] / hDg] tfkj|md, b]Vg ;lsg]
g;lsg] cflbdf Wofg lbg eGg'xf];\ .

x ;d"xut ¿kdf k:| tt' ug{ nufpgx' f];\ . klxnf] ;dx" n] k:| tt' u/s] f u0' fx¿
gbf]xf]l/g] u/L cGo ;Df"xnfO{ k|:t't ug{ nufpg'xf;] \ / cfjZos k[i7kfi] f0f
lbgx' f;] \ .

x bl[ i6ljxLg ljBfyL{x¿nfO{ ;d]t pkofu] x'g] u/L lgdf{0f ePsf] af]Ng]
ydf]{ld6/sf] af/d] f ;d]t hfgsf/L u/fO{ k|bzg{ ug{ nufpg'xf;] \ .

-u_ dN" ofª\sg
x ydf]{ld6/ egs] f] s] xf] < of] sg' l;4fGtdf cfwfl/t eP/ agfOPsf] xG' 5 <
x ydf{]ld6/sf] ;kmf lrq agfpm .
x kf/f] / cNsfx] nlar km/s 5'6o\ fpm .
x plDn/xs] f] kfgLsf] tfkjm| d gfKg cNsfx] n ydfl{] d6/sf] ;66\ f kf/fo] 'St
ydf]ld6/ k|ofu] ul/G5 . lsg <

-3_ kl/of]hgf sfo{
x c;fwf/0f tfkj|mddfks oGqsf] ;kmf gfdfª\lst lrq agfpg nufpg'xf];\ .

-ª_ k|fljlws zAbfjnL
aNaM ydfl{] d6/sf] t/n kbfy{ /fVg ko| f]u ul/Psf] kftnf] sfFrsf] gnL

-r_ lzIfssf nflu yk ljifoj:t'
s'g} klg ydf{l] d6/n] To;df ko| f]u ul/Psf] t/n kbfy{sf] Freezing Point eGbf tnsf]
accurate tfkj|md gfKg ;Sb}g lsgeg] ha t/n kbfy{ hD5 o;sf] contraction x'g]
kl| jm| of klxn] h:tf] uniform xg' ;Sbg} . To:t} Boiling Point kl5 t/n kbfy{ Uof;F
eO{ c0f'x¿ :jtGq¿kdf rnfodfg xg' ] xFb' f pSt ydfl]{ d6/n] s'g} lglZrt reading
lbg ;Sbg} . cNsfx] n pDng] tfkjm| d 78 C ePsfn] cNsf]xnoS' t ydf]l{ d6/n]
plDn/xs] f] kfgLsf] tfkjm| d gfKg ;lsbF g} . lsgls plDn/xs] f] kfgLsf] tfkjm| d
cNsfx] n pDng] tfkjm| deGbf pRr xG' 5 t/ kf/f]sf] pDng] tfkj|md 357 C ePsf]n]
kf/fo] 'St ydf]{ld6/n] plDn/xs] f] kfgLsf] tfkj|md ;lhn} gfKg ;S5 . To;}n] plDn/xs] f]
kfgLsf] tfkjm| d gfKg kf/f]o'St ydf]{ld6/ ko| fu] ul/G5 .
lxdfndf w/] } lr;f] xG' 5 / tfkjm| dsf] dfg C0ffTds klg xG' 5 . kf/fs] f] hDg] tfkjm| d
-39 C / cNsf]xnsf] hDg] tfkjm| d -115 C ePsfn] kf/f]o'SteGbf cNsf]xno'St
ydf{l] d6/ Gog" tfkj|md gfKg a9L pko'St xG' 5 . ;fy} of] kf/f]eGbf ;:tf] klg k5{ .
To;}n] lxdfn cf/fx] Lx¿n] cNsfx] n ydf{l] d6/ k|ofu] u5g{ .

53

tfkLo ;Gtn' g (Thermometer Equillibrium)
s'g} tftf] j:tn' fO{ lr;f] j:t;' uF /fvd] f jf lr;f] j:tn' fO{ tftf] j:t';Fu /fv]df lr;f]
j:t'lt/ tfk kj| fx xG' 5 . Pjd /Ltn] cGTodf tfk kj| fx aGb x'G5 / bj' } j:t' ;dfg
tfkjm| ddf /xG5g\ . To:tf j:t'x¿nfO{ tfkLo ;Gt'ng (thermal Equillibrium) df
/x]sf j:tx' ¿ elgG5 .
t;y{ ;dfg tfkj|mddf /xs] f j:tx' ¿nfO{ tfkLo ;Gtn' gdf /x]sf eg/] a'lemG5 .
tfkLo ;Gtn' g sfod ug{sf] nflu hlxn] klg pRr tfkj|md ePsf] j:ta' f6 sd -
lgDg_ tfkjm| d ePsf] j:tl' t/ tfk k|jfx xG' 5 .
lbg 3: tfkj|mddfks oGqdf :sn] lgwf/{ 0f (Calibration in thermometer)
-s_ ljlzi6 p2]Zo

x tfkj|mddfks oGqdf :sn] lgwf{/0fsf] kl/ro lbg
x tfkjm| ddfks oGqdf dflyNnf] / tNnf] crn laGb'nfO{ kl/eflift ug{
x ko| fu] åf/f tfkj|mddfks oGqdf dflyNnf] / tNnf] crn laGb'sf] dfg kTtf

nufpg
-v_ l;sfO ;xhLs/0f lj|mofsnfk
lj|mofsnfk 1 tfkjm| ddfks oGqsf] dflyNnf] / tNnf] crn laGb'

x ljBfyL{x¿nfO{ ;f]Rg] hf8] L agfpg] / cge' j cfbfgk|bfg ug]{ tl/sf k|of]u
u/L tfkj|mddfks oGq (thermometer) b]vfpFb} o;sf] dflyNnf] / tNnf]
crn laGb' tyf :sn] lgwf{/0faf/d] f 5nkmn u/fpgx' f;] \ .

x 5nkmndf ;xhLs/0f ub{} dflyNnf] / tNnf] crn laGb'nfO{ :ki6;Fu kl/eflift
ul/lbgx' f];\ .

ljm| ofsnfk 2 tfkj|md dfks oGqdf dflyNnf] / tNnf] crn ljGb'sf] dfg
x ljBfyL{sf] ;xeflutfdf kf7\ok':tssf] lj|mofsnfk 2 sf] lrq g=+ 6.2 df lbP
h:t} u/L ;fduL| tof/ ug{x' f];\ / k|of]uåf/f dflyNnf] crn laGb' gf6] ug{
nufpg'xf;] \ .

k|ofu] ljlw -s_ dflyNnf] crn laGb'sf] dfg
Pp6f /fp08 a6d km\Nof:s df 2/3 ldlnln6/ hlt kfgL /fvL b'O{ cf6] f
Kjfn ePsf] ss{ lkm6 ug{]
pSt km\Nof:snfO{ l6«k]8 :6\ofG8df hfnL /fvL To;df a;fpg] .
kmN\ of:snfO{ c8fpg o;sf] 3f6LnfO{ :6o\ fG8;uF hf8] \g]
ca ss{nfO{ Air tight u/L Pp6f Kjfndf ydf{]ld6/ / csf]{ Kjfndf L
cfsf/sf] Delivery tube hf]8L lkm6 ug]{ -ydf{]ld6/ bulb / tube sf] 5p] n]
kfgL 5g' x' F'b}g_

54

ca kfgLnfO{ Sprit Lamp n] lj:tf/} ttfpg] -o;f] ubf{ ydfl]{ d6/sf] kf/f]
lj:tf/} dfly r9b\ } hfG5 / Pp6f lglZrt laGb'df uP/ l:y/ /xG5 . of] g}
dflyNnf] crn laGb' 1000C cyjf 2120F xf] .

x To;u} /L ljm| ofsnfk 3 df ljBfyL{x¿sf] ;xeflutf u/fpgx' f;] \ . ko| fu] sf]
cfwf/df tNnf] crn laGb' dfkg ug{ nufpgx' f;] \ .

Kfo| f]u ljlw -v_ tNnf] crn laGbs' f] dfg
Pp6f ;fn] LnfO{ :6\ofG8df c8fP/ To;sf] d'lg Pp6f vfnL las/ /fVg'xf];\ .
ca ;f]nLdf a/kmsf 6'j|mfx¿ /fVgx' f];\ / lardf ydf]l{ d6/sf] k"/} aNa 5f]lkg]
u/L 3;' fpgx' f];\ . o;f] ul/;sk] l5 ydf]l{ d6/df /x]sf] kf/f] cjnfs] g ug{
nufpgx' f;] \ .
kf/fs] f] prfO la:tf/} 36\b} hfG5 / lglZrt laGb'df uP/ l:y/ /xG5 . of] g}
tNnf] crn laGb' 00C cyjf 320F xf] .

x DfflyNnf] / tNnf] crn laGb' kTtf nufO;sk] l5 ;]lN;o; :sn] / km/]gxfO6
:s]ndf v08 v08 ¿kdf afF8g\ ] tl/sfaf/] 5nkmn u/L ki| 6 kfl/lbg'xf;] \ .

-u_ dN" ofª\sg
x ydf{]ld6/df :s]n lgwf/{ 0f eGgfn] s] al' emG5 <
x dflyNnf] / tNnf] crn laGb'nfO{ kl/eflift u/ . logLx¿sf] dfg slt slt
x'G5 < ;l] N;o; / km/g] xfO6 :sn] bj' }df n]v .
x dflYfNnf] crn laGb' / tNnf] crn laGba' Lr leGgtf 56' \ofpm .

-3_ kl/ofh] gf sfo{
ydfl{] d6/df dflyNnf] crn laGb' / tNnf] crn laGbs' f] lgwf/{ 0f ug{] ljlw lrq;lxt
k:| t't ug{ nufpg'xf];\ .
ª_ kf| ljlws zAbfjnL
1. Standard Atmospheric pressure = ;dG' bL| ;txdf jfos' f] rfk jf

Aof/fl] d6/df kf/f]sf] prfO 760 mm Hg xbF' f jfo'd08ndf cjl:yt rfk, o;sf]
dfg

= 1.013×105N/M2 or pa

2. dflyNnf] crn laGb' M 1000C cyjf 2120F
3. tNnf] crn laGb' M 00C cyjf 320F

55

lzIfssf nflu yk ljifoj:t'
Tfkjm| d / o;sf] gfk ;DaGwL cWoog ug]{ lj1fgnfO{ ydf{d] 6] L« (Thermometry)
elgG5 .
;d'b| ;txdf jfo'd08nLo rfk a9L x'g] xF'bf o;n] Aof/fl] d6/df /xs] f] kf/f]sf]
prfOnfO{ pRrtd ljGb' 760 mm ;Dd y]Ug ;S5 .
ds{/L Aof/f]ld6/ ko| f]u u/L rfk gfKg' egs] f] kf/f]sf] prfO gf6] u/L tnsf] ;q" ko| f]u
ug{' xf] .
p= hdg hxfF p = rfk, h = Jof/f]ld6/df Mercury sf] prfO, d = kf/fs] f] 3gTj /
g= u'?Tjfsif{0faf6 xg' ] k|j]u
lbg 4: tfkj|mdsf PsfOx¿sf] ¿kfGt/0f
-s_ ljlzi6 p2Z] o

x tfkj|md dfkgsf :sn] / PsfOx¿ atfpg
x ;]lN;o; / km/]gxfO6larsf] ;DaGw ;dLs/0fsf ¿kdf JoSt ug{
x ;l] N;o; / km/]gxfO6 PsfOnfO{ Ps csfd]{ f ¿kfGt/0f ug{
-v_ l;sfO ;xhLs/0f lj|mofsnfk
lj|mofsnfk 1 tfkj|md dfkgsf :sn] x¿ / PsfOx¿

x ljBfyL{nfO{ cfkm"n] hfg]sf] tfkjm| dsf :sn] -PsfO_ x¿ eGg nufpgx' f];\ /
lgDgfg';f/ k|Zgx¿ ;fW] gx' f];\ .

;l] N;o; :sn] df a/km kUng] / kfgL pDng] tfkj|md slt slt xG' 5 <
ltgLx¿larsf] tfkjm| d slt v08df aFfl8Psf] xG' 5 <

km/g] xfO6 :sn] df tNnf] / dflyNnf] crn laGb'sf] dfg slt slt xG' 5 <
ltgLx¿larsf] tfkj|md slt v08df ljeflht x'G5 <

x ljBfyL{af6 k|fKt hjfkmnfO{ 5nkmn ub{} yk :ki6 xg' ] u/L pTt/
atfOlbgx' f;] \ .

x ;l] N;o; / km/]gxfO6 :sn] larsf] ;DaGw ;dLs/0fnfO{ zI} fl0fs kf6Ldf
n]Vg'xf];\ .

=

x Kff7o\ k:' tssf] pbfx/0f 1 / ʹ jf ;f] h:t} ;d:of nv] L ljBfyLn{ fO{
;]lN;o;nfO{ km/g] xfO6df / km/g] xfO6nfO{ ;l] N;o; PsfOdf abNg
nufpg'xf;] \ / cfjZos ki[ 7kfi] f0f lbg'xf];\ .

56

-u_ dN" ofªs\ g

lgDg k|Zgx¿ ;fw] /] dN" ofªs\ g ug{'xf];\ M

x ;l] N;o; :s]ndf tNnf] / dflyNnf] crn laGbs' f] dfg slt dflgG5 <
x ;]lN;o; / km/]gxfO6larsf] ;DaGw hgfpg] ;dLs/0f n]Vf .
x -40°C a/fa/ slt km/g] xfO6 xG' 5 <
x 98.6° F nfO{ ;]lN;o; PsfOdf abn .

-3_ kf| ljlws zAbfjnL

x ;l] N;o; M tfkjm| dsf] To:tf] OsfO h;df tNnf] crn laGb' / dflyNnf]
crn laGb' j|mdzM 00C / 1000C dflgG5 .

x km/]gxfO6 M tfkjm| dsf] To:tf] OsfO h;df tNnf] crn laGb' / dflyNnf]
crn laGb' j|mdzM 320F / 2120F dflgG5 .

-ª_ lzIfssf nflu yk ljifoj:t'

x ljleGg lsl;dsf tfkjm| dsf :sn] x¿

Tffkjm| dsf] :sn] tNnf] dflyNnf] ljefhg ul/Psf]
crn laGb' crn laGb' v08sf] ;ª\Vof

;l] N;o; -;]lG6u8]| _ 0 C 100 100
180
km/]gxfO6 32 212 100

sl] Neg (Absolute 273K 373 K 80

temperature scale)

l/pd/ :sn] (Reaumer 0 R 80 R

Scale)

x Tffkj|mdsf PsfOsf ;DaGw hgfpg] ;dLs/0f

== =

lbg 5: tfkj|mddfks oGqsf lsl;dx¿ (Types of Thermometers)

-s_ ljlzi6 p2]Zo

x agfj6 / sfdsf cfwf/df ydfl]{ d6/sf lsl;d / gfdx¿ atfpg
x lSnlgsn ydfl]{ d6/sf] agf6] / sfo{ k|0ffnL JofVof ug{
x ;fwf/0f ydf{]ld6/sf] agf6] / sfd JofVof ug{

-cf_ l;sfO ;xhLs/0f lj|mofsnfk

ljm| ofsnfk 1 lSnlgsn ydf{]ld6/

57

x sIffsf] cfsf/ / ljBfyL{ ;ªV\ ofcg';f/ ;dx" ljefhg ug'x{ f;] \ .
x ljBfyL{x¿nfO{ agfj6 / sfdsf cfwf/df ydf{l] d6/sf lsl;dx¿ / gfd

atfpbF } k|Tos] ;d"xnfO{ 1/1 cf6] f lSnlgsn ydfl]{ d6/ ljt/0f u/L cjnfs] g
ug{ nufpg'xf];\ / lgDgfg';f/ k|Zg ;fW] g'xf];\ .
-c_ ydf{]ld6/df s'g sg' :sn] agfOPsf] 5 <
-cf_ aNalg/ lsg ;f3F /' f] 3fF6L agfOPsf] 5, lsg <
-O_ of] s:tf] cfsf/ 5 <

-O_{ o;df sltb]lv slt;Dd :sn] agfOPsf] 5 < - df / df _

x ljBfyLx{ ¿af6 kf| Kt hjfkmnfO{ yk :ki6 kfb}{ k|Zgsf pTt/ lbFb} lSnlgsn
ydfl]{ d6/ agf6] / sfdaf/] yk ki[ 7kfi] f0f lbg'xf];\ .

x dfly plNnlvt kT| os] ;d"xsf 1/1 hgf ljBfyL{sf] z/L/sf] tfkjm| d gfKg
nufpgx' f];\ . of] sfddf lzIfsn] ;xhLs/0f ub}{ tfkj|md gfKg l;sfpgx' f];\ .

lj|mofsnfk 2 ;fwf/0f ydf]{ld6/

x ljBfyLx{ ¿nfO{ k|ofu] zfnfsf] tfkj|md dfks oGq -;fwf/0f ydf{]ld6/_ k|bz{g
ug'xf;] \ . o;;Fu ;DalGwt kZ| gx¿ ;fW] gx' f;] \ . -;Dej eP;Dd k|To]s
aG] rut ¿kdf Pp6f Pp6f ydf]l{ d6/ ljt/0f u/L cjnf]sg ug{ nufpg'xf;] _\

1= o;df slt bl] v slt ;Ddsf] :sn] x'G5 <

2= of] s:tf] cfsf/sf] x'G5 <
3= aNasf] aflx/L efu kftnf] sfrF n] agfPsf] x'G5 , lsg <
x sx] L ljBfyL{x¿af6 k|Zgsf] pTt/ lng'xf];\ . To;kl5 yk JofVof ub}{ ;fwf/0f

ydfl{] d6/sf] agf6] / sfoa{ f/] atfOlbgx' f;] \ .
x kT| os] aG] r jf 6]an' ut ¿kdf lSnlgsn / ;fwf/0f ydf]l{ d6/df s] s] km/s

5 xf]nf < 5nkmn ug{ nufO{ leGgtf rf6{ tof/ u/L k:| tt' ug{ nufpgx' f];\ .
x ;d"ut ¿kdf k|:tt' ubf{ cfjZos k[i7kfi] f0f k|bfg ug'{xf];\ .
-u_ dN" ofªs\ g
x lSnlgsn ydf]{ld6/ eg]sf] s] xf] < o;df ;]lN;o; :sn] sltbl] v slt;Dd

xG' 5 <
x :j:y dflg;sf] z/L/sf] tfkj|md slt xG' 5 < -oC / oF bj' } :s]ndf n]Vf_
x lSnlgsn ydfl{] d6/sf] aNalg/ 3f6F L ;f3/'F f] agfOPsf] xG' 5, lsg <
x lSnlgsn ydf]l{ d6/ uf]nf] geO{ lkH| dl] 6s cfsf/sf] xg' fn] s] kmfObf xG' 5 <

58

x ;fwf/0f ydf]l{ d6/df sltbl] v slt;Dd :s]n agfPsf] x'G5 <
x ydf{]ld6/sf] aNasf] aflx/L efu kftnf] sfrF n] agfOPsf] xG' 5, lsg <
-3_ kl/ofh] gf sfo{
ltd|f] 3/sf ;a} JolStsf] z/L/sf] tfkjm| d lSnlgsn ydf]l{ d6/ k|of]u u/L gfk /
s;}nfO{ Hj/f] cfPsf] jf gcfPsf] kTtf nufpm . -o;sf nflu ljBfno jf :jf:Yo
;:+ yfsf] ydf{l] d6/ k|of]u ug{ ;lsG5 ._
-ª_ yk cWoog ;fduL|
x ljleGg l;4fGtdf agfOPsf] / ko| fu] ePsf] kbfy{sf] cfwf/df ydf]l{ d6/sf

lsl;dx¿
1. t/no'St ydfl{] d6/ (Liquid thermometer)
-c_ kf/f]oS' t ydf]l{ d6/ (Mercury thermometer)
-cf_ cNsfx] no'St ydf{]ld6/ (Alcohol thermometer)
2= UofF; ydfl]{ d6/ (Gas thermometer)
3= cj/f]w ydfl{] d6/ (Resistance Thermometer)
4= tfk ljB'tLo ydfl]{ d6/ (Thermo electric thermometer)
5= ljls/0f ydf{]ld6/ (Radiation thermometer )
6= jfik rfk ydfl{] d6/ (Vapour pressure thermometer)
-r_ ;Gbe{ ;fduL|

1. Physics.tutorvista.com/heat/temperature/html
2. www.physicsclassroom.com/class/thermalp
3. www.cyberphysics.co.uk/topics/heat/thermometer.htm
4. Principles of physics , Grade XI

59

PsfO 7 : ks| fz (Light)

cgd' flgt 3G6L M 6 - 5;}4flGts ± 1 ko| fu] fTds_

1= l;sfO pknlAw

x P]gf / o;sf k|sf/x¿ -;dtn / uf]nfsf/_ sf] kl/ro lbO{ aj|m Pg] faf6 xg' ]

k/fjtg{ sf] kb| z{g ug{

x Jff:tljs / cjf:tljs cfsl[ tsf] kl/ro lbg / k|bz{g ug{

x Uffn] fsf/ P]gfaf6 ljleGg b'/Ldf -cgGtdf / aj|mtfsf] s]Gb| k5fl8_ /xs] f

j:ts' f] cfsl[ t agfO{ kb| zg{ ug{ / ls/0f /]vflrq lvRg

x Uffn] fsf/ Pg] fsf] pkofl] utf j0fg{ ug{

x k|sfz cfjt{gsf] kl/efiff;lxt kl/ro lbg
2= ljifoj:t' ljefhg / l;sfO ;fdu|L

lbg ljifoj:t' l;sfO ;fduL|

1 Pg] f / o;sf ks| f/x¿ M ;dtn P]gf, sGse] P]gf, sGeS] ; P]gf,
;dtn P]gf / ufn] fsf/ Pg] f lrq g+= 7.5 / 7.6 agfOPsf] rf6{ k]k/,
cªu\ h]| L tyf g]kfnL cIf/ nl] vPsf]
ˆNof; sf8{x¿ 2

2 Jff:tljs / cjf:tljs cfs[lt sGs]e P]gf, sGe]S; Pg] f, ;dtn P]gf,
ufn] fsf/ P]gf;uF ;DalGwt ;t] f] afSnf] sfuh lrq g+= 7.7
sx] L dxTTjk"0f{ zAbfjnL
agfOPsf] rf6{ kk] /

3 sGse] Pg] fsf] /v] flrq sGse] P]gf, sDkf;, sDkf; k]g jf
:s]n

4 sGe]S; Pg] fsf] /]vflrq / sGe]S; Pg] f, sDkf;, sDkf; k]g jf
Pg] fsf pkof]lutf rs, :sn]

5 k|sfzsf] cfjt{g, o;sf] sf/0f Unf; :Nofa, las/, kfgL, lunf; jf
lgodx¿ / c;/x¿ sk, l;Ssf, l;;fsnd

6 ko| f]ufTds sfo{M 1= sGse] 1= sFfrsf] :Nofa, ;dtn 6]a'n, ;]tf]
Pg] faf6 jf:tljs cfsl[ t sfuh, lkgx¿, :sn]
agfO{ s]Gb|Ls/0f b'/L gfKg] 2= sGs]e P]gf, ;]tf] afSnf] sfuh, :s]n
2= ks| fzsf] cfjt{g ljm| ofsf]
kl' i6 ug{]

3= ljlzi6 p2Z] o, l;sfO ;xhLs/0f lj|mofsnfk / dN" ofª\sg

60

lbg 1. P]gf / o;sf ks| f/x¿ -;dtn Pg] f / ufn] fsf/ P]gf_
-s_ ljlzi6 p2Z] o

x ks| fzsf] ls/0f / ls/0fk~' hsf] kl/efiff lbg
x P]gfsf] kl/ro lbO{ o;sf ks| f/x¿ atfpg
x ;dtn Pg] fnfO{ kl/eflift u/L o;af6 aGg] cfs[ltsf u'0fx¿ eGg
x sGse] / sGeS] ; Pg] fsf] kl/ro lbO{ ltgLx¿af6 x'g] k/fjtg{ sf] kb| z{g /

JofVof ug{
-v_ l;sfO ;xhLs/0f ljm| ofsnfk
lj|mofsnfk 1 ls/0f, ls/0fk'~h, P]gf / P]gfsf ks| f/x¿

x ;jk{ y| d ljBfyL{x¿nfO{ sIff 7 df ks| fzsf] kf7df l;ss] f s/' fx¿sf]
kg' /fj[lTtsf nflu k|Zg ub{} ls/0f / ls/0fk'~hsf] kl/efiff / ;ª\st] k\mNof;
sf8{dfk{mt k'g/fj[lTt u/fpg'xf];\ .

x ljBfyL{x¿nfO{ ljleGg lsl;dsf P]gf / ltgLx¿sf] ko| f]u;DaGwL cge' jx¿
eGg nufpgx' f];\ . ;f] j|mddf ;xhLs/0f ub{} P]gfnfO{ lgDgfg';f/ kl/eflift
ul/lbg'xf];\ . æj:ta' f6 cfPsf] ks| fznfO{ k/fjtg{ u/L To; j:t'sf] cfs[lt
agfpg] pks/0fnfO{ Pg] f elgG5 .Æ

x ljleGg lsl;dsf Pg] fx¿ kb| zg{ ub}{ dV' otof ;dtn / uf]nfsf/ u/L b'O{
k|sf/sf P]gfx¿ x'G5g\ egL atfOlbgx' f];\ .

x ljBfyL{x¿nfO{ ;dx" df ljefhg u/L ;dtn Pg] fx¿ ljt/0f u/L To;sf] lrq,
kl/ro / sfd ;DaGwdf 5nkmn ug{ nufO{ k:| tt' ug{ nufpgx' f;] / lgDg
lgisif{ lbgx' f;] \ .

lgisif{ M j:t'af6 cfPsf] ks| fznfO{ k/fjtg{ ug]{ ;tx ;dtn ePsf] P]gfnfO{ ;dtn
P]gf elgG5 . o; ks| f/sf] Pg] f xfdLn] 3/df cfk\mgf] cgx' f/ x]g{ / gx' fpg] sf7] fdf
k|ofu] ul/G5 .
lj|mofsnfk 2 ;dtn P]gfsf] u0' fx¿

x ljBfyL{x¿nfO{ cfjZos ;ªV\ ofdf ljefhg ug{x' f];\ / kT| os] ;d"xnfO{ Ps Ps
cf6] f ;dtn P]gf ljt/0f ugx{' f];\ .

x tTkZrft\ ljm| ofsnfk 1 ug{ nufO{ sIffdf k|bz{g ug{ nufpg'xf;] \ .
x lj|mofsnfk 1 sf] kb| z{gkZrft ;dtn Pg] faf6 aGg] cfs[ltsf u'0fx¿sf]

;"rL tof/ kfg{ nufO{ k:| t't ug{ nufpgx' f;] \ .
x cªu\ |h] L tyf gk] fnL cIf/ nl] vPsf kmN\ of; sf8{sf] cfsl[ t bv] fO{ yk k|i6

kfl/lbg'xf];\ .

61

ljm| ofsnfk 3 uf]nfsf/ P]gf

x ljBfyL{x¿nfO{ cfjZos ;ª\Vofdf ljefhg u/L kT| o]s ;d"xnfO{ Pp6f Pp6f
l:6nsf] rDrf ljt/0f ug'{xf;] \ / /fd/| L cjnf]sg ug{ nufO{ blaPsf] / p7s] f]
efusf] gfd tyf b]lvg] cfs[lt klxrfg ug{ nufpgx' f;] \ .

x ljBfyL{x¿af6 k|fKt k|ltlj|mofx¿sf] cfwf/df Uffn] fsf/ P]gf klg sGse] /
sGeS] ; u/L bO' { lsl;dsf xG' 5g\ egL atfpgx' f];\ .

x lrq g=+ 7.5 df agfOPsf] rf6{ kk] / / sGse] Pg] f kb| zg{ ub{} pSt P]gfaf6
xg' ] k/fjt{gaf/] j0f{g ul/lbgx' f;] \ .

ljm| ofsnfk 4 sGe]S; / sGs]e P]gf

x lrq g+= 7.6 df agfOPsf] rf6{ k]k/ / sGe]S; Pg] f kb| z{g ub{} pSt Pg] faf6
x'g] k/fjt{gsf] JofVof ug{ nufpg'xf;] \ .

x ljBfyL{x¿n] k|:tt' u/]sf cge' jx¿nfO{ ;d6] b\ } lgDg lgisif{ lbgx' f;] \ M

lgisif{ M sGs]e P]gfn] o;df k/]sf ks| fzsf ls/0fx¿nfO{ s]lGbt| ug{] ePsfn]
o;nfO{ sG] bL| s/0f Pg] f (converging mirror) elgG5 eg] sGe]S; P]gfdf
;dfgfGt/ k|sfzsf ls/0fx¿ k/fjt{g eO{ 5l/P/ /xg] cyft{ \ ljs]lGb|t xg' ]
ePsfn] o;nfO{ ljsl] Gb|t P]gf (diverging mirror) elgG5 .

ljm| ofsnfk 5 sGs]e P]g / cfs[lt

x ljBfyL{nfO{ Pp6f sGs]e Pg] f lng nufP/ 50 cm hlt 6f9f /fVg
nufpgx' f];\ / To;df pgLx¿sf] cg'xf/ x]g{ nufpgx' f];\ .

x km] l/ P]gfnfO{ glhs Nofpg nufpg'xf];\ tyf klxn] / clxn] s] km/s bl] vG5
;fW] g'xf];\ .

x Pg] fnfO{ ce}m glhs Nofpg nufpg] / x]g{ nufpg] . ca s] km/s kfOof,]
cgx' f/ 7'nf] bl] vof] ls ;fgf,] cgx' f/ pN6f] b]lvof] ls ;'N6f,] 6f9faf6 glhs
NofpbF f cfs[ltdf s] km/s kfOof,] eGg nufpgx' f];\ / cfjZos lgisif{
lbg'xf];\ .

-u_ dN" ofª\sg
x ks| fzsf] ls/0f / ls/0fk~' hsf] ;ªs\ t] ;lxt kl/efiff eg .
x ;dtn P]gf egs] f] s] xf] < ;dtn P]gfaf6 aGg] cfsl[ tsf u'0fx¿ s] s] xg' \ <
x cgx' f/ x]g{ s'g ks| f/sf] Pg] f ko| fu] ul/G5 <
x lrq;lxt sGse] / sGe]S; Pg] fsf] kl/efiff n]v .
x 6r{nfO6df /flvPsf] Concave P]gfsf] s]Gb|laGb'df aNa /flvPsf] x'G5 .
o;af6 6r{nfO6sf] ko| f]u ubf{ s] kmfObf xG' 5 <
x df6] /;fOsn jf uf8Lsf] ;fO8 P]gfsf ¿kdf bfofF afofF xg] { Concave
Pg] fsf] k|ofu] ugs'{ f] sf/0f s] xf] <

62

-3_ kl/ofh] gf sfo{
sGse] P]gfnfO{ s]GbL| s/0f Pg] f / sGeS] ; P]gfnfO{ ljs]Gb|Ls/0f P]gf klg elgG5 .
o;sf] sf/0f vN' g] u/L lrq;lxt sf8a{ f]8{ kk] /df tof/ ug{ nufO{ k:| tt' ug{
nufpgx' f];\ .
-ª_ kf| ljlws zAbfjnL

x sG] b|Ls/0f ljGb' (Focus) M Tof] laGb' hxfF ks| fzsf ls/0f Pslqt xG' 5g\
cyjf hxfaF f6 k|sfzsf ls/0f lkmFlhPsf xG' 5g\ .

x Laterally Inverted M cfsl[ tdf j:ts' f] bfofF efu afoftF km{ / afofF efu
bfofFtkm{ b]lvg'

-r_ lzIfssf nflu ljifoj:ts' f] yk ki[ 7kfi] f0f
x Concave mirror sf] leqL efunfO{ reflecting surface elgG5 .
x Convex mirror sf] aflx/L efunfO{ reflecting surface elgG5 .
x Plane mirror n] agfPsf] cfs[lt laterally inverted xg' 'sf ;fy} j:t'sf] b/' L
object distance / cfs[ltsf] b/' L image distance a/fa/ xG' 5 .
x Mirror n] ks| fzsf ls/0fnfO{ reflection u/]kl5 image agfpF5 .

lbg 2: jf:tljs / cjf:tljs cfs[lt (Real and virtual image)

-s_ ljlzi6 p2]Zo
x sGs]e Pg] fn] agfpg] ljleGg cfsl[ tx¿sf] cjnf]sg ug{
x jf:tljs / cjf:tljs cfs[ltsf] kl/ro lbg
x sGse] P]gf k|of]u u/L jf:tljs cfs[lt kb| zg{ ug{
x jf:tljs / cjf:tljs cfsl[ tlar km/s 5'6\ofpg

-v_ l;sfO ;xhLs/0f ljm| ofsnfk
ljm| ofsnfk 1 sGs]e Pg] f / j:t'sf] cfsl[ t

x Pp6f sGse] Pg] f lnO{ To;nfO{ em\ ofnaflx/ kmsf{pg nufpgx' f;] \ .
x Pg] fsf] cufl8 20-30 cm sf] b'/Ldf Pp6f ;]tf] afSnf] sfuh /fVg

nufpg'xf];\ .
x ca P]gfaf6 k/fjtg{ ePsf ls/0fx¿ pSt sfuhdf kfg{ nufpg'xf;] \ .
x P]gfnfO{ cufl8 jf k5fl8 ;f//] aflx/sf j:ts' f] cfsl[ t sfuhdf ki| 6 b]lvg]

agfpg nufpgx' f];\ .

63

x o; cj:yfdf sfuh / Pg] flarsf] b/' L gfKg nufpg'xf;] \ / ;f] b/' Ls]GbL| s/0f
b'/L (focal length) elgG5 egL ki| 6 kfg{x' f;] \ .

x o;/L sGse] P]gfåf/f sfuhdf ags] f] cfsl[ t jf:tljs cfs[lt xf] / sGse]
P]gfn] 7n' f], ;fgf], pN6f], ;'N6f,] jf:tljs / cjf:tljs ;a} lsl;dsf cfsl[ t
agfp5F egL ki| 6 kfgx'{ f;] \ .

x jf:tljs / cjf:tljs cfsl[ tsf] kl/ro lbb} sGse] P]gf j:ts' f] jf:tljs
cfsl[ t agfpg ;Sg] t/ sGeS] ; / ;dtn P]gfn] jf:tljs cfs[lt agfpg
g;Sg] s'/f atfOlbg'xf;] \ .

ljm| ofsnfk 2 jf:tljs / cjf:tljs cfs[lt

x dflysf] ljm| ofsnfk Pssf] cfwf/df jf:tljs / cjf:tljs cfs[lt egs] f] s]
xfn] f < ;f]Rg] hf]8L agfpg] / cge' j cfbfgkb| fg ug{ nufpgx' f;] \ / oL b'O{
larsf] km/snfO{ tnsf] tflnsf zI} fl0fs kf6Ldf agfpgx' f;] \ .

Real image Virtual image

x The image can be captured 1. The image cannot be captured in a

in a screen screen.

x The image is always 2. The image is always erect.

inverted.

x Light rays actually meet to 3. Light rays donot actually meet to

form a real image. form a virtual image.

x kf7o\ k:' tssf] lrq g=+ 7.7 agfOPsf] rf6{ kk] / kb| z{g ub{} uf]nfsf/ P]gf;uF

;DalGwt dxTTTjk0" f{ zAbfjnLx¿sf] hfgsf/L u/fpg'xf];\ .

x gofF l:6nsf] rDrfsf] Concave / Convex ;txdf lgofn/] xg] {] / cgx' f/b]lv

rDrfsf] b'/L 36a9 ubf{ b]lvg] cfkm\gf] cfsl[ t s:tf] xG' 5, ljBfyL{nfO{
cjnf]sg ug{ nufO{ Real / Virtual image sf] concept lbgx' f;] \ .

64

x P]gfdf d'xf/ xb] f{ bl] vg] cfsl[ t cjf:tljs ePsfn] sfuhdf kfg{ jf ptfg{
;lsFb}g . To:t} telescope / microscope n] lbg] cfsl[ t klg kbf{df ptfg{
;lsFb}g egL ki| 6\ofpg'xf;] \ . P]gfsf] s]Gb|, aj|mtfsf] s]Gb,| jjm| tfsf] cw{Jof;,
kd| v' cIf, s]GbL| s/0f laGb' / s]Gb|Ls/0f b'/Lsf] :ki6;uF lrq z}Ifl0fs kf6Ldf
agfO{ ;ª\st] x¿df 5nkmn u/fpg'xf];\ .

-u_ dN" ofªs\ g
x jf:tljs / cjf:tljs cfsl[ tlar km/s 5'6o\ fpm .
x s:tf] lsl;dsf] Pg] fn] jf:tljs cfs[lt agfpg ;S5 <
x tnsf zAbfjnLsf] kl/efiff / ;ªs\ ]t n]v .
i_ k|dv' cIf ii _ sG] b|Ls/0f ljGb' iii _ aj|mtfsf] s]Gb|

-3_ kl/ofh] gf sfo{
lstfasf] lrq g=+ 7.7 sf8{af]8{df ptf/L uf]nfsf/ P]gf;uF ;DalGwt dxTTTjk"0f{
zAbfjnLx¿sf] ;r" L tof/ ug{ nufpgx' f;] \ .
-ª_ kf| ljlws zAbfjnL
Centre of Curvature : Concave jf convex mirror nfO{ k"0f{ uf]nfsf/ ;lDemFbf To;sf]
s]Gb|
Radius of curvature : P]gf k0" f{ ufn] fsf/ xF'bfsf] cj:yfdf o;sf] cw{Jof;
Focal length : Focus / Pole larsf] b'/L

65

lbg 3 sGse] Pg] fsf] /]vflrqx¿

-s_ ljlzi6 p2Z] o

x ls/0f /]vflrqsf] kl/ro lbg
x sGse] Pgfsf] /]vflrq lvRg cfjZos lgodx¿ atfpg
x sGse] Pg] faf6 ljleGg b'/Ldf -cgGtdf / ajm| tfsf] s]Gbe| Gbf k/_ /xs] f

j:ts' f] cfs[lt agfO{ ls/0f /]vflrq lvRg / cfsl[ tsf ljz]iftfx¿ atfpg

-v_ l;sfO ;xhLs/0f ljm| ofsnfk

lj|mofsnfk 1 sGse] Pg] fsf] /]vflrq lvRg cfjZos lgodx¿
x sGs]e P]gfsf] /]vflrq lvRg' cufl8 z}Ifl0fs kf6Ldf ;/n lrq sf/] /] lgDg
lgodx¿sf] 5nkmn ub{} ljBfyL{x¿nfO{ k|i6 kfgx'{ f];\ .
k|dv' cIf;uF ;dfgfGt/ k|sfzsf ls/0fx¿ sGs]e Pg] faf6 k/fjt{g eO{
s]GbL| s/0f ljGb'af6 hfG5g\ .
sG] bL| s/0f laGba' f6 cfPsf k|sfzsf ls/0fx¿ sGs]e P]gfaf6 k/fjt{g xb'F f
k|d'v cIf;uF ;dfgfGt/ eP/ hfG5g\ .
aj|mtfsf] s]Gba| f6 cfPsf] k|sfzsf] ls/0f ;f]xL af6f] kms{G5g\ .

ljm| ofsnfk 2 sGse] P]gfaf6 aGg] /v] flrq
x kf7o\ k:' tssf] ljm| ofsnfk 5 df lbOPsf] tl/sfx¿ atfpbF } j:tn' fO{ sGs]e
P]gfsf] jjm| tfsf] sG] b| C eGbf k/ /fVbf aGg] cfsl[ tsf] /]vflrq zI} fl0fs
kf6Ldf sDkf;, sDkf; kg] jf rs / :sn] k|of]u u/L lvFRb} hfgx' f];\ /
ljBfyLn{ fO{ klg ;Fu;Fu} /]vflrq lvRg nufpg'xf;] \ . -kf7o\ k:' tssf] lrq g=+
7.10_
x /]vflrq tof/ eO;s]kl5 cfsl[ tsf ljz]iftfx¿ atfpg nufpgx' f];\ .
x To;u} /L j:tn' fO{ cgGtdf /fVbf aGg] cfs[ltsf] /]vflrq lvRg l;sfpg'xf;] \ /
ljBfyL{nfO{ cfsl[ tsf u0' fx¿ eGg nufpg'xf];\ . (lrq g+= 7.11)
x cGTodf sGse] Pg] faf6 aGg] cfsl[ tsf] ;fOh, :yfg / ks| [lt j:t' /flvPsf]
:yfgcg';f/ km/s–km/s xG' 5 eGg] s'/f atfOlbg'xf];\ .
x b[li6ljxLg ljBfyL{x¿nfO{ /]vflrqaf/] hfgsf/L lbg lrqdfly wfuf] 6fF;]/ :kz{
u/fpgx' f;] \ .

-u_ d"Nofªs\ g

x sGse] Pg] fn] s:tf] cfs[lt agfp5F < lsg <
x sGse] Pg] fsf] /v] flrq lvRg cfjZos lgodx¿ s] s] x'g\ < ;r" L tof/ kf/ .
x ajm| tfsf] sG] b| C eGbf k/ /fVbf sGs]e P]gfn] s:tf] cfsl[ t agfpF5 <

/v] flrq;lxt cfs[ltsf] ljz]iftf -ks| [lt_ n]v .

66

-3_ kl/ofh] gf sfo{
x j:t'nfO{ lgDg :yfgdf /fVbf sGs]e Pg] faf6 aGg] cfs[ltsf /]vflrq A4
size paper df agfpg nufO{ cfsl[ tsf ljz]iftfx¿ klg n]vL sIffdf k|bzg{
ug{ nufpg'xf];\ .

-c_ cgGtdf
-cf_ aj|mtfsf] sG] b| C eGbf k/ /fVbf
-ª_ lzIfsnfO{ yk ki[ 7kfi] f0f
Ray diagram nfO{ draw ug{] j|mddf mirror agfpgsf nflu compass sf] k|of]u u/L
nfdf] radius lnP/ curve agfpFbf lrq /fd|f] bl] vG5 .

lbg 4 sGe]S; Pg] fsf] /]vflrq
-s_ ljlzi6 p2Z] o

x sGeS] ; Pg] fsf] /v] flrq lvRg cfjZos lgodx¿ kfngf atfpg
x j:t'nfO{ ljleGg :yfgdf -cgGtdf, Pg] fsf] sG] b| P / cgGtsf] lardf_ /fVbf

aGg] sGe]S; P]gfsf] /]vflrq agfO{ cfsl[ tsf] ljz]iftfx¿ atfpg
x uf]nfsf/ P]gfsf] pkof]lutfx¿ atfpg
-v_ l;sfO ;xhLs/0f ljm| ofsnfk
lj|mofsnfk 1 sGeS] ; P]gfsf] /v] flrq lvRg cfjZos lgodx¿
x ljBfyL{x¿nfO{ kf7o\ k':tssf] lrq g=+ 7.13 cjnf]sg ug{ nufpg'xf];\ /

zI} fl0fs kf6Ldf ;d]t pSt /v] flrq sf]//] sGe]S; P]gfsf] /]vflrq lvRg
cfjZos lgDg lgodx¿ / tl/sfx¿df 5nkmn u/fpg'xf;] \ .
o sGeS] ; P]gfdf sG] b|Ls/0f ljGb'(F) / jj|mtfsf] s]Gb|(C) Pg] fsf]

k5fl8lt/ kb{5 .
o k|dv' cIf;uF ;dfgfGt/ k|sfzsf] ls/0f P]gfaf6 k/fjt{g x'Fbf s]Gb|Ls/0f

ljGb'af6 cfPsf] h:tf] b]lvG5 .
o ajm| tfsf] sG] b|lt/ uPsf] ks| fzsf] ls/0f ;f]xL af6f] eO k/fjtg{ xG' 5 .
ljm| ofsnfk 2: sGe]S; Pg] sf] /v] flrq
x j:t'nfO{ cgGtdf /fVbf sGe]S; Pg] fn] agfpg] cfsl[ tsf] /]vflrq sDkf;,
sDkf; k]g jf rs / :s]nsf] ko| fu] u/L zI} fl0fs kf6Ldf agfpFb}

67

ljBfyL{x¿nfO{ k|bzg{ ug{'xf;] \ / pgLx¿nfO{ klg sfkLdf ug{ nufpgx' f;] \ . -
kf7\ok':tssf] lrq g+ 7.14_
x /v] flrq agfpg l;sfPkl5 To;df ePsf cfs[ltsf ljzi] ftfx¿ n]Vg
nufpgx' f];\ .
x To;}u/L j:t'nfO{ P]gfsf] s]Gb| / cgGtsf] lardf /fVbf aGg] cfsl[ tsf] klg
/v] flrq agfO{ cfs[ltsf] k|s[lt k:| t't ug{ nufpgx' f];\ . -lrq g=+ 7.15_
x bl[ i6ljxLg ljBfyL{x¿nfO{ /v] flrq af/] hfgsf/L lbg lrqdfly wfuf] 6fF;]/
:kz{ u/fpg'xf;] \ .
ljm| ofsnfk 3: ufn] fsf/ P]gfsf] pkofl] utf -sGse] / sGeS] ; P]gf_
x ljBfyL{x¿nfO{ b'|t n]vg (Quick write) tl/sf ckgfO{ uf]nfsf/ Pg] f -sGs]e
/ sGe]S;_ sf] Ps Ps pkofl] utf nV] g nufpgx' f;] \ .
x kfnk} fnf] ljBfyL{x¿nfO{ k|:tt' ug{ nufpg'xf];\ / z}Ifl0fs kf6Ldf l6kf]6 ub}{
hfgx' f;] \ . -ljBfyL{nfO{ kfn}kfnf] k:| t't ug{ nufpFbf gbfx] l/g] u/L k:| t't ug{
lgbz]{ g lbg'xf];_\
x ljBfyL{x¿sf] cg'ejx¿nfO{ ;d6] \b} uf]nfsf/ Pg] fsf] pkofl] utfsf ;DaGwdf
yk ki[ 7kf]if0f lbgx' f;] \ .
-u_ dN" ofªs\ g
x sGe]S; P]gfsf] /v] flrq lvRg s'g s'g lgodx¿sf] h?/t k5{ <
x sG] bL| s/0f ljGb' P]gfsf] k5fl8 k5{ eg] Tof] sg' lsl;dsf] Pg] f xf] <
x j:tn' fO{ Pg] fsf] s]Gb| / cgGtsf] lardf /fVbf sGeS] ; Pg] fn] s:tf]
lsl;dsf] cfsl[ t agfp5F < /]vflrq;lxt ks| [lt nv] .
x sGs]e P]gfsf] 3 cf6] f pkof]lutfx¿ n]v .
x sGeS] ; P]gfsf] 2 cf6] f pkof]lutf atfpm .
x ;f}o{ rn' f]df sGse] Pg] f ko| f]u ul/G5, lsg <
-3_ kl/of]hgf sfo{
ltd|f] ljBfno, ufp,F ;x/ jf a;f]af; :yfg glhs uf]nfsf/ P]gfsf] pkof]u sg' s'g
sfddf ePsf] 5 < cWoog u/L 5f6] f] l/kf]6 n]v .
-ª_ lzIfssf nflu yk k[i7kf]if0f
sGse] Pg] fn] o;df k/s] f ;dfgfGt/ k|sfzsf ls/0fx¿nfO{ k/fjtg{ u/L Pp6}
ljGbd' f sl] Gbt| ub5{ . kmn:j¿k ;"o{af6 cfPsf ks| fzsf ls/0fx¿ Ps} 7fpdF f sl] Gb|t
eO{ k|z:t dfqfdf tfkzlSt hDdf x'G5 . To;}n] ;o" {af6 cfjZos tfkzlSt hDdf ug{
;fo} { rn' fd] f sGse] Pg] f ko| fu] ul/G5 .

68

lbg M 5 k|sfzsf] cfjtg{ , o;sf sf/0f, lgod / c;/x¿

-s_ ljlzi6 p2]Zo
x k|sfzsf] cfjtg{ sf] kl/efiff lbg / o;sf] sf/0f atfpg
x ;3g / la/n dfWodsf] kl/efiff lbg / klxrfg ug{
x k|sfzsf] cfjt{gsf lgodx¿ pNnv] ug{
x k|sfzsf] cfjt{gsf c;/x¿ atfO{ ltgLx¿sf] sf/0f JofVof ug{

-v_ l;sfO ;xhLs/0f ljm| ofsnfk
ljm| ofsnfk 1 ks| fzsf] cfjt{gsf] cjwf/0ff / sf/0f

x ljBfofyLx{ ¿nfO{ lgDgfg';f/ k|Zgx¿ ;f]Wb} 5nkmn u/fpgx' f];\ .
-c_ kfv] /Lsf] kfgLsf] ulx/fO{ jf:tljseGbf sd b]lvG5, lsg <
-cf_ kfgLdf cfwf 8'afPsf] n6\7L ;txlt/ efF lrPsf] h:t} jf afª\uf] bl] vG5, lsg <
x 5nkmndf ;xhLs/0f ub{} dfly ;fl] wPsf h:t} b}lgs hLjgdf cge' j ul/g]

cGo 36gfx¿ atfpg nufpgx' f;] \ . oL 36gfx¿sf] JofVof ug{ k|sfzsf]
cfjt{g ljm| ofsf af/d] f hfGg' cfjZos /x]sf] s/' f atfOlbgx' f;] \ .
x ks| fzsf] cfjtg{ / o;sf] sf/0faf/d] f sIffsf7] fdf aG] rut jf 6]anu' t
¿kdf 5nkmn u/fO{ k|:t't ug{ nufpgx' f];\ .
x ljBfyLn{ ] k|:tt' u/s] f cge' jnfO{ ;d]6L lgisif{ k|:t't ug{x' f];\ .
ljm| ofsnfk 2 k|sfzsf] cfjt{g ljm| ofsf] c;/
x kf7o\ k:' tsdf ePsf] ljm| ofsnfk 7 / 8 sf] k|ofu] u/L ljBfyL{nfO{ kb| zg{ ub{}
cjnf]sg u/fpg'xf];\ .
Pp6f sfFrsf] lunf;df cfwf hlt kfgL /fvL To;df Pp6f l;;fsnd 58\s]
kf/]/ 8a' fpgx' f;] \ / ljBfyL{nfO{ kfgLdfly / kfgLleqsf] l;;fsndsf] efunfO{
Psk} 6s bl] vg] u/L x]g{ nufpg'xf];\ .
km]l/ csf]{ vfnL lunf;df Pp6f l;Ssf /fVg'xf];\ . ljBfyL{nfO{ cjnfs] g ug{
nufpFb} To;df lj:tf/} kfgL vGofpFb} hfg'xf;] \ .
ljBfyL{nfO{ cjnfs] g u/L bl] vPsf] tYo eGg nufpgx' f;] \ . ca ljBfyL{n]
l;SsfnfO{ klxn]eGbf dfly p7s] f] bV] g5] g\ / o; tYojf/] yk hfgsf/L
u/fpgx' f];\ .
hfgsf/L M k|sfzsf] cfjt{g lj|mofsf] sf/0fn] j:ta' f6 cfPsf k|sfzsf ls/0fx¿ kfgL
-;3g dfWod_ af6 xfjf -la/n dfWod_ lt/ cfpbF f gdn{ af6 6f9f afªl\ uP/ cfO{ xfdf| ]
cfF vfdf kg{] x'gfn] xfdLn] ljm| ofsnfk 7 / 8 df eP h:t} cge' j u5f}{ eGg] s/' f

69

k|i6;uF JofVof ul/lbgx' f;] \ . ;fy} ;'?df ;fw] ]sf 2 cf]6f cge' j ;DaGwL kZ| gx¿sf]
sf/0f klg ks| fzsf] cfjtg{ s} c;/ ePsf] s/' f lrq;lxt JofVof ul/lbg'xf;] \ .
ljm| ofsnfk 3 ks| fz cfjt{gsf lgodx¿sf] ko| fu]

x lkg, 8O« ª af]8{, l;;fsnd, ;t] f] sfuh / Unf;, :Nofa h:tf ;fdu|Lx¿
;ªs\ ng ug{ nufpg'xf];\ / o;df cfwfl/t lgDg l;4fGtx¿ k|i6 kfgx{' f];\ .

– cfkltt ls/0f, cfjlt{t ls/0f / gdn{ Pp6} ;txsf] Pp6} laGb'df k5g{ \ .
– ks| fzsf] ls/0f la/n dfWodaf6 ;3g dfWoddf hfFbf gd{nlt/ / ;3g

dfWodaf6 la/n dfWodlt/ hfFbf gdn{ b]lv 6f9f afªl\ uG5 .
x ;t] f] sfuh lngx' f;] \ / To;nfO{ drawing board df yd lkgsf] ;xfotfn]

6fF:gx' f;] \ . sfuhsf] lardf Unf; :Nofa /fv]/ To;sf] jl/kl/ l;;fsndn]
;fjwfgLk"js{ A, B, C, D lrx\g nufpgx' f;] \ . AB ;fO8sf] sl/a Ps ltxfO{
efudf ljGb' O lrxg\ nufpgx' f];\ / To;df MN n]en lvRgx' f];\ . gdn{ ;Fu i
l8uL| xg' ] u/L cfkltt ls/0f IO lvRgx' f;] \ / b'O{ cf6] f lkgx¿ (P / Q) nfO{
uf8\g'xf];\ . ca, Unf; :NofanfO{ klxn] h:t} u/L sfuhdf lvlrPsf] /v] f
ABCD leq kg]{ u/L /fVg'xf;] \ . Unf; :Nofasf] csf{] ;fO8af6 ckltt
ls/0faf6 uf8]sf lkg (P / Q) nfO{ xg] x{' f];\ / l;wf xg' ] u/L csf]{ bO' { cf]6f
lkg (S / T) nfO{ uf8g\ 'xf];\ . Unf; :NofanfO{ lems]/ lkg ul8Psf ljGb'x¿
(S / T) nfO{ hf8] g\ x' f;] \ . /]vf ST nfO{ R ;Dd nDAofpg'xf;] \ . To;u} /L O / R
nfO{ klg hf]8g\ x' f];\ . -lrq M kf7o\ k:' tssf] kh] g+ 68_
lgisif{
x/s] dfWoddf ks| fzsf] ult km/s km/s xg' ] ePsfn] dfWod kl/jtg{ xF'bf
ks| fz afª\luG5 .
-u_ d"Nofª\sg
x k|sfzsf] cfjt{g egs] f] s] xf] < o;sf] sf/0f s] xf]nf <
x ;3g dfWod / lj/n dfWodlar pbfx/0f;lxt km/s 5'6\ofpm .
x ks| fzsf] cfjtg{ sf lgodx¿ s] s] xg' \ <
x sf/0f bp] m M
(i_ kfgLdf cfwf 8'afPsf] l;;fsnd afª\uf] b]lvG5 .
(ii_ kfv] /Lsf] kfgLsf] ulx/fO{ jf:tljs ulx/fOe{ Gbf sd b]lvG5 .
x kfgLleq bl] vPs} :yfgdf efnf xfg]/ df5fnfO{ dfg{ ;lsPnf < sf/0f;lxt
pTt/ b]pm .

70

-3_ kl/of]hgf sfo{
k|sfzsf] cfjtg{ sf] sf/0fn] ubf{ b}lgs hLjgdf cg'ej ul/g] % cf]6f tYox¿sf]
cjnfs] g u/L l6kf]6 tof/ ug{ nufpg'xf];\ .
-ª_ k|fljlws zAbfjnL
ks| fzsf] cfjtg{ M ks| fz Ps dfWodaf6 csf{] dfWoddf hfbF f afªl\ ug] k|lj|mof
;3g dfWod M tn' gfTds ¿kdf a9L 3gTj ePsf] dfWod
lj/n dfWod M t'ngfTds ¿kdf sd 3gTj ePsf] dfWod
-r_ lzIfsnfO{ yk k[i7kfi] f0f

x a9L 3gTj ePsf] x sd 3gTj ePsf]
x k|sfzsf] ult sd x ks| fzsf] ult a9L
x o; dfWoddf kj| z] ubf{ ks| fz x o; dfWoddf k|j]z ubf{ k|sfz

gd{nlt/ emS' 5 . gd{naf6 6f9f hfG5 .

lbg 6: ko| fu] fTds sfo{

-s_ ljlzi6 p2Z] o

x sGse] Pg] faf6 kbfd{ f jf:tljs cfs[lt agfO{ k|bz{g ug{ / lrq agfO{ pSt
P]gfsf] s]Gb|Ls/0f b'/L gfKg

x Unf; :Nofasf] ko| fu] u/L ks| fzsf] cfjt{g ljm| of / o;sf lgodx¿ kl' i6 ug{

-v_ l;sfO ;xhLs/0f lj|mofsnfk

lj|mofsnfk 1 sGs]e / sGe]S; Pg] faf6 aGg] cfsl[ tsf] ko| f]u

x sIffsf] cfsf/ / ljBfyL{ ;ªV\ ofcg;' f/ ljBfyL{x¿sf] ;d"x lgdf{0f ug{'xf;] \ .
x k|Tos] ;d"xnfO{ 1/1 cf6] f sGse] P]gf ljt/0f u/L kf7\ok:' tssf] ljm| ofsnfk

4 cg;' f/ ug{ nufpg'xf;] \ / cfjZos ;xhLs/0f ug{x' f];\ .

71

x Pp6f sGe]S; n]G;nfO{ em\ofnlt/ kmsf{pg nufpg'xf;] \ . ca Pg] fsf] 20-30
cm sf] b/' Ldf ;t] f] afSnf] sfuh /fvL k/fjlt{t ls/0fnfO{ To;df kfg{
nufpgx' f;] .

x ha sfuhdf aflx/sf j:ts' f] cfs[lt k|i6 ¿kdf bl] vG5 ta sfuh / Pg] fsf]

larsf] b'/L gfKg nufpgx' f];\ . o; b'/LnfO{ sG] bL| s/0f b/' L (focal length)
elgG5 . oL cfs[ltx¿ kbfd{ f ptfg{ ;lsPsfn] jf:tljs cfsl[ t (real
image) x'g\ egL atfOlbgx' f];\ .

x ljBfyLx{ ¿nfO{ klg kfnk} fnf] ;]tf] kbfd{ f j:t'sf] cfs[lt agfO{ k|bz{g ug{ ufO{
lrq agfpg nufpgx' f];\ .

lj|mofsnfk 2 k|sfzsf] cfjtg{ sf] lgodsf] k|ofu]

x dfly plNnlvt kT| os] ;dx" nfO{ 1/1 cf]6f sFfrsf] :Nofa kb| fg ugx'{ f;] \ /
kf7o\ k':tssf] lj|mofsnfk 6 df eg] cg;' f/ ug{ nufpg'xf;] \ . o;f] ubf{
kT| o]s ;d"xnfO{ ;xof]u ugx'{ f;] \ .

x ljm| ofsnfkkl5 ;t] f] sfuhdf tof/ ePsf] lrq lstfasf] lrq g=+ 7.16 ;uF
bfF Hg nufpgx' f;] \ .

x ko| fu] sf cfwf/df k|sfzsf] cfjt{g ljm| of ki| 6;Fu JofVof u/L lgodx¿ nV] g
nufpgx' f;] \ / ;t] f] sfuhdf ePsf] lrqsf] cfwf/df cfkltt ls/0f (incident
ray), cfjltt{ ls/0f (refracted ray) / Odh]G{ 6 ls/0f (emergent ray) sf]
gfd n]Vg nufpgx' f];\ .

-u_ d"Nofªs\ g

x jf:tljs cfs[lt egs] f] s] xf] < s:tf] Pg] fn] j:t'sf] jf:tljs cfsl[ t
agfpg ;S5 <

x s:tf] cj:yfdf sfuh / Pg] flarsf] b'/L s]GbL| s/0f b/' L xG' 5 <

x sFfrsf] :Nofa / xfjfdWo] sg' rFflx ;3g dfWod xf] / lsg <

x k|sfzsf] cfjtg{ sf lgodx¿ s] s] x'g\ <

x tnsf] /v] flrq k/" f u/ . M

A

xfjf

B

sFfrsf] :Nofa

N

72

x leGgtf atfpm M
-i _ la/n dfWod / ;3g dfWo

-ii_ jf:tljs cfs[lt / cjf:tljs cfs[lt
-iii) sGs]e Pg] f / sGeS] ; Pg] f

-3_ yk cWoog ;fdu|L
;dtn P]gfdf xfd|f] cfsl[ t bl] vg] t/ klqsf k9\bf klqsfdf cfsl[ t gb]lvg] sf/0f M
;dtn Pg] fn] lgoldt k/fjtg{ ub5{ / cfs[lt agfpg ;S5 t/ klqsfsf] ;tx
;dtn gePsfn] lgoldt k/fjtg xF'bg} . To;}n] xfd|f] cfsl[ t bl] vFb}g .
j:t'nfO{ ljleGg :yfgdf /fVbf sGs]e P]gfn] agfpg] cfsl[ tx¿sf yk /v] flrqx¿ M
-c_ C df /fVbf

jf:tljs, pN6f], j:t' hq} / C df aG5 . –
-cf_ C / F sf] lardf /fVbf

– jf:tljs
– pN6f]
– 7'nf]
– C eGbf k5fl8
-O_ F df /fVbf

– jf:tljs
– pN6f]
– w/] } 7n' f]
– C eGbf k5fl8

-O_{ F / P sf] lardf /fVbf
– cjf:tljs
– 7f8f]
– w/] } 7n' f]

– Pg] feGbf k5fl8

73

-s_ kf]v/Lsf] kfgLleq /x]sf] df5f jf:tljs :yfgeGbf dfly bl] vg] sf/0f

Dffgf}F, kf]v/Lleq /xs] f] df5fsf] jf:tljs :yfg
AB 5 . df5fsf] b'O{ 5]p A / B af6 cfPsf
cfkltt ls/0fx¿ kfgLsf] dfWod x'bF } ;txaflx/
xfjfsf] dfWoddf hfF bf k|sfzsf] cfjtg{ sf]
sf/0fn] gdn{ af6 6f9f afªl\ uP/ xfdf| ] cFfvfdf
kb{5 . o:tf] lj|mofn] ubf{ xfdLn] df5fnfO{
jf:tljs :yfg AB eGbf s]xL dflysf] :yfg
A'B' df b]V5fF} . To;}n] k|sfzsf] cfjtg{
lj|mofn] ubf{ kf]v/Lsf] df5f jf:tljs :yfgeGbf dfly b]lvG5 .
-v_ kfgLdf cfwf 8a' fPsf] l;;fsnd afª\uf] bl] vG5 . kfgLdf
l;;fsnd 8'afpFbf afªu\ f] bl] vg] k|sfzsf] cfjtg{ sf] sf/0fn] xf]
. ks| fzsf] ls/0f kfgLaf6 (denser medium) xfjf (rarer
medium) df cfpFbf, normal af6 afª\luP/ hfG5, ;f] sf/0fn]
cfs[lt jf:tljs :yfgeGbf dfly aGb5 / afª\uf] bl] vG5 .
k|sfzsf] cfjtg{ sf] lgod -:gn] sf] lgod_
sg' } bO' {cf6] f dfWodsf] nflu, cfkltt sf0] fsf] sine sf] dfg / cfjlt{t sf]0fsf] sine
sf] dfgsf] cg'kft ;wF} l:y/ xG' 5 / pSt l:y/ dfgnfO{ klxnf] dfWodsf] tn' gfdf
bf];|f] dfWodsf] l/k|mflS6e OG8S] ; (Refractive index) elgG5 . o;nfO{ u|Ls cIf/ 'μ'
n] hgfOG5 .

P Sini hxFf, i = cfkltt sf]0f, r = cfjltt{ sf0] f

Sin r

xfjfsf] t'ngfdf,
-c_ kfgLsf] l/km| flS6e OG8S] ; Ö 1.33
-cf_ sFfrsf] l/k|mflS6e OG8S] ; Ö 1.55

– lj|mofsnfk 6 sf] ko| f]udf ‘i / ‘r sf] dfg kTtf nufP/ sFfrsf]
l/k|mflS6e OG8]S; klg kTtf nufpg ;lsG5 .

-ª_ ;Gbe{ ;fduL|

1. http://www.physicsclassroom.com/class/refln
2. http://www.physicsclassroom.com/class/refrn
3. http://www.physicsclassroom.com/mmedia/optics
4. Principles of physics, Grade – XI.

74

PsfO 8 Wjlg (sound)

cgd' flgt 3G6L M 3 (2 ;4} flGts + 1 ko| f]ufTds_
1= l;sfO pknlAw

x Wjlg ;DaGwL zAbfjnLx¿ -ult, cfj[lTt / t/ª\u nDafO_ sf] kl/ro lbg

x Kfl| tWjlg / u'~hfodfg c;/sf] kl/ro lbg, c;/ atfpg / km/s 5'6o\ fpg

2= ljifoj:t' ljefhg / l;sfO ;fduL|

lbg ljifoj:t' l;sfO ;fdu|L

1 Wjlg t/ªu\ , t/ªu\ nDafO, cfj[lTt / Wjlg pTkfbg ug{] ljleGg j:tx' ¿
Wjlgsf] ju] h:t} M nfdf] l:kª| l;7L 6\ol' gª

kmf]s{ cflb .

2 Wjlgsf] k/fjt{g, kl| tWjlg u'~hfodfg, Kfl| tWjlg / u~' hfodfg k|bzg{
k|ltWjlg ;DaGwL ;/n ul0ftLo ;Df:of ;DaGwL >Job[Zo ;fduL|

3 k|of]ufTds ljm| ofsnfk :6k jfr

3= ljlzi6 p2]Zo, l;sfO ;xhLs/0f lj|mofsnfk, dN" ofªs\ g

lbg 1 M Wjlg t/ªu\ , t/ª\u nDafO / cfjl[ Tt
-s_ ljlzi6 p2]Zo

x Wjlg / Wjlg t/ªu\ sf] kl/ro lbg

x Wjlgsf] k;| f/0f k|ljm| of atfpg

x t/ª\u nDafO / cfjl[ TTfsf] kl/ro lbg

x Wjlgsf] j]u cfj[lTt / t/ªu\ nDafOlarsf] ;DaGw atfpg / ul0ftLo
;d:of ;dfwfg ug{

-v_ l;sfO ;xhLs/0f lj|mofsnfk

lj|mofsnfk 1 Wjlgsf] kl/ro / k;| f/0f

x ljBfyLx{ ¿nfO{ sIffsf7] fdf pknAw ljleGg ;fdu|Laf6 Wjlg pTkGg ug{
nufpgx' f];\ . h:t} M af]n]/, l;7L ahfP/, 8:6/n] 6]andf lk6/] , 6\o'lgª
kmf]sn{ ] /a/ ss{df 7fs] /] cflb .

x dflysf] lj|mofsnfk;Fu ;DalGwt lgDg k|Zgx¿df 5nkmn u/fpgx' f;] \ .

75

Wjlg s] xf] <
Wjlg s;/L pTkGg x'G5 <
Wjlg k|;f/0f xg' s]sf] h?/t k5{ xfn] f <
x 5nkmnsf] cfwf/df lgisif{ k|:tt' ug'x{ f];\ M j:t'sf] sDkgaf6 Wjlg pTkGg

xG' 5 . j:t'sf] sDkg x'Fbf t/ª\ux¿ pTkGg eO{ ltg} t/ªux¿af6 Wjlg
zlStsf] k;| f/0f xG' 5 . Wjlg pTkGg x'g dfWod -7f];, t/n / Uof;F _ sf]
h?/t k5{ .
x b'O{ hgf ljBfyLn{ fO{ Pp6f nfdf] l:kª| NofO{ tGsfpg nufpg] / Ps 5]p
;dft]sf] ljBfyLn{ fO{ lj:tf/} tlGsPsf] l:kª| df xfGg nufpg] / csf{] ljBfyLn{ ]
s] cg'ej u5{ < eGg nufpgx' f;] \ .
x ljBfyL{x¿af6 k|fKt kl| tlj|mofx¿nfO{ ;d6] \b} k|of]usf] lgisif{ atfpg'xf;] \ .
lgisif{ M hxfF lxsfP{ sf] xf] ToxfF t/ª\u pTkGg x'G5 / tL t/ªu\ x¿ k/fjt{g
eO{ k'gM klxn]s} 7fpFdf kmsG{ 5g\ . t/ªu\ k|;f/0f xF'bf l:k|ªsf rSsfx¿ bfofF
afofF sDkg ePsf] b]lvG5 . t/ªu\ pTkGg ePsf] 7fpsF f l:k|ªsf rSsfx¿
vflF bG5g / To;kl5sf rSsfx¿ km'S5g\ . of] jm| d 5p] ;Dd xG' 5 . kml] /
vflF bPsf rSsfx¿ km'S5g\ eg] kms' ]sf rSsfx¿ vflF bb} hfG5g\ . oltan] f
rSsfx¿sf] sDkg / t/ªu\ k;| f/0fsf] lbzf Pp6} xG' 5 . o; lsl;dsf]
t/ªu\ nfO{ nª\luRo'l8gn (Longitudinal wave) t/ª\u elgG5 . vflF bPsf]
l:k|ªsf] efunfO{ compression / kms' ]sf] efunfO{ rarefaction elgG5 .
x Wjlgsf] t/ªu\ nDafO, cfj[lTt / ju] nfO{ tkl;nsf] lrq z}Ifl0fs kf6Ldf
agfO{ 5nkmn u/fpg'xf];\ . ;fy} ltgLx¿sf] ;ª\s]t / PsfOx¿ klxrfg ug{
nufpg'xf;] \ .

t/ªu\ nDafO -O_

Speaker

t/ªu\ nDafO (Wave length)
x lrqsf] cfwf/df 5nkmn kZrft\ lgDg lgisif{ lbgx' f;] \ M t/ªu\ k;| f/0f x'Fbf

Pp6f vfFlbPsf c0fa' f6 ;a}eGbf glhssf] csf]{ vflF bPsf c0f;' Ddsf] b'/LnfO{
jf km' s]sf] c0fa' f6 ;a}eGbf glhssf] k'ms]sf] c0f;' Ddsf] b'/LnfO{ Ps t/ªu\

76

nDafO elgG5 . o;nfO{ O n] hgfOG5 / ld6/ PsfOdf gflkG5 . kl| t
;s] ]G8 pTkGg xg' ] k"0f{ t/ªu\ sf] ;ª\VofnfO{ cfjl[ Tt elgG5 . o;nfO{ f n]
hgfOG5 . o;sf] PsfO xh{ (Hertz) xf] h;nfO{ Hz n] hgfOG5 .

x Wjlgsf t/ªu\ nDafO, cfj[lTt / ju] larsf] ;DaGw

Wjlgsf] j]u (V) = cfjl[ Tt (f)× t/ª nDafO -O_

kg' /fj[lTt u/fO{ kf7\ok':tssf] pbfx/0f 1 / 2 jf ;f] h:t} ;fwf/0f ul0ftLo ;d:of
agfO{ ;dfwfg ug{ nufpgx' f;] \ / cfjZos ;xhLs/0f ug{x' f];\ .

ljm| ofsnfk 2 7f]; dfWoddf Wjlg k;| f/0f x'G5 eGg] s'/fsf] kb| z{g

x nfdf] wfuf], bO' { cf]6f ;nfOsf vfnL a66\ fx¿, bO' { cf]6f ;nfOsf sf6F Lx¿
lng'xf;] \ .

x ca b'O{ cf6] f ;nfOsf vfnL a66\ fx¿ lng'xf;] \ / kT| os] sf] lkwF df Kjfn
kfg'x{ f];\ .

x Kjfnaf6 wfuf] l5/fO{ afWF gx' f;] \ / leqkl6\6af6 ;nfOsf] sf6L c8s\ fpgx' f];\ /
To:t} csf{] k6l\ 6sf] a6\6fdf klg ugx{' f;] \ .

x ljBfyLn{ fO{ hf8] L hf8] Ldf a:g nufO{ Pp6f a66\ f cfkm" n] ;dfO{ csf]{ a66\ f
;fyLnfO{ ;dfpg nufpg] / sfgsf] glhs /fvL cfkm" n] ;fgf] :j/n] af]Ng /
;fyLnfO{ ;'Gg nufpg] ug{x' f];\ .

x Aflx/f ljBfyL{x¿nfO{ sDkg / t/ª\u k;| f/0fsf] af/d] f hfgsf/L lbg sDkgsf]
:kz{ u/fpg'xf;] \ .

x afn] s] f] Ps csf{n] ] ki| 6;Fu ;G' g ;s] g;s]sf] jf/] ;fW] g] / 5nkmn u/L
lgisifd{ f k'Ug'xf;] \ . -af]Ng] ;dodf wfuf] tlGsPsf] x'g'k5{ ._

lgisif{ M Wjlg 7f;] dfWodaf6 /fd/| L k;| f/0f x'G5 .

-u_ d"Nofª\sg

x Wjlg t/ªu\ s;/L k;| f/0f xG' 5 < of] s'g lsl;dsf] t/ª\u xf] <

x nª\luRo'l8gn t/ª\u egs] f] s] xf] <

x kl/efiff PsfO / ;ªs\ t] nV] f .

(i_ t/ª\u nDafO -ii_ cfjl[ Tt -iii_ Wjlgsf] ju]

x 3.3 m t/ª\u nDafO ePsf] Wjlgsf] ju] 330m/s eP cfj[lTt slt x'G5 <

x Wjlg t/ªu\ sf] cfjl[ Tt 80 HZ 5 eGgfn] s] a'lemG5 <

x 15 m t/ª\u nDafO ePsf] Wjlgsf] cfj[lTt 100 Hz eP ;f] Wjlgsf] ju] slt

xG' 5 < [pTt/ M 1500 m/s]

77

-3_ kl/ofh] gf sfo{
ljBfyL{nfO{ cfkm" /x]sf] Ifq] df /xs] f] jf ;'lgg] Pkm= Pd /l] 8ofx] ¿sf] cfj[lTt slt slt
/x5] < kTtf nufO{ ;r" L tof/ kfg{ nufO{ sIffdf k|:t't ug{ nufpgx' f;] \ .
-r_ lzIfssf nflu yk k[i7kfi] f0f
nª\luRol' 8gn t/ªu\ sf ljzi] ftfx¿

x dfWodsf s0fx¿sf] sDkgsf] lbzf / t/ªu\ k;| f/0fsf] lbzf Pp6} x'G5 .
x ;a} s0fx¿sf] PDklNRo8' , cfj[lTt / cjlw Pp6} xG' 5 .
x 7f];, t/n / UofF; ;a} dfWoddf k|;f/0f xg' ;S5 .
x Wjlg vflF bPsf] / km'ss] f] >]0fLx¿sf] ¿kdf k|;f/0f x'G5 .
x vflF bPsf] efudf rfk / 3gTj clwstd / kms' ]sf] efudf Gog' td xG' 5 .

xfjfdf k;| f/0f eO/xs] f] nªl\ uRo'gn t/ªu\

lbg 2. Wjlgsf] k/fjtg{ , kl| tWjlg / u'~hfodfg tyf k|ltWjlg ;DaGwL

;/n ul0ftLo ;d:of

-s_ ljlzi6 p2]Zo

x Wjlgsf] k/fjt{g / u~' hfodfgsf] kl/ro lbg
x k|ltWjlg / u~' hfodfgaLr km/s 5'6\ofpg
x k|ltWjlg ;DaGwL ;/n ul0ftLo ;d:ofx¿ xn ug{

-v_ l;sfO ;xhLs/0f ljm| ofsnfk

ljm| ofsnfk 1 Wjlgsf] k/fjtg{ , k|ltWjlg / u~' hfodfg

78

x lgDglnlvt k|Zgx¿ ;f]Wb} ljBfyL{nfO{ cfˆgf cge' jx¿ ;g' fpg'xf];\ /
pgLx¿sf] cge' j klg ;g' fpg nufpgx' f];\ .

cUnf] kxf8 jf kx/fsf] cufl8 vfF]r jf ;'g;fg hªu\ nsf] lardf a;]/
s/fpbF f s] xG' 5, lsg <

vfnL / 7'nf sf]7fdf afN] bf cfjfh s:tf] ;'lgG5, lsg <
rf}/df af]Nbf / vfnL sf]7fdf af]Nbf s] km/s k5{ <
x Wjlgsf] k/fjt{ g, k|ltWjlg / u~' hfodfg ;DaGwL lel8of] kb| zg{ ug{'xf];\ /

ljBfyL{x¿nfO{ /fd|/L cjnfs] g ug{ nufpg'xf];\ .
x Wjlgsf] k/fjt{g, k|ltWjlg / u'~hfodfg ;DaGwdf lel8of]df cjnf]sg

u/s] f kIfx¿sf] af/d] f ljBfyL{nfO{ k|:tt' ug{ nufpg'xf;] \ / lgisif{ k];
ug'x{ f;] \ .
lgisif{
– ha Wjlgsf t/ªu\ x¿ 3/sf] leTtf, kxf8sf] ;tx, r66\ fgsf] ;tx h:tf
s'g} s8f tyf ;dtn ;txdf 7Ss/ vfG5g\ ta t/ª\ux¿ k/fjtg{ x'G5g\ .
Wjlgsf t/ª\ux¿ k/fjt{g xFb' f logn] ks| fzsf t/ªu\ x¿sf k/fjtg{ sf
lgodx¿ kfngf u5g{ \ . 7'nf] sf]7f jf xn cflbsf Wjlg k/fjtg{ 7f];
j:t'x¿df 7f]lsP/ xG' 5 . sg' } s8f ;txdf 7Ss/ vfO{ kmls{g] WjlgnfO{
Wjlgsf] k/fjt{g elgG5 .
– Wjlgsf] k/fjt{gsf] sf/0f kl| tWjlg (Echo) kb} f x'G5 . ha s'g} ;|f]taf6
lg:ss] f] Wjlg 6f9f /xs] f] 3/sf] leTtf, kxf8sf] ;txdf 7Ss/ vfO{ k/fjt{g
eO{ bfx] f]/f] ;'lgG5 o:tf] WjlgnfO{ kl| tWjlg (Echo) elgG5 . o;u} /L 6f9f
/xs] f] kxf8sf] vf]r, ulx/f] Ogf/ tyf kvfn{ cflbdf klg o:t} ;l' gG5 .
o;/L kl| tWjlg xbF' f bfx] f]/f] cfjfh k|i6 ;'lgG5 .
– Wjlg lglZrt b'/Lsf] sg' } ;txdf 7Ss/ vfO{ k/fjt{g eP/ ;l' gg] WjlgnfO{
kl| tWjlg (Echo) elgG5 . k|ltWjlg x'g Wjlgsf] ;f| ]t / k/fjtg{ xg' ]
;txlarsf] b/' L 17m eGbf a9L xg' k' 5{ .
– olb k/fjtg{ ug]{ ;tx Wjlgsf] ;|ft] 17m eGbf glhs 5 eg] k/fjlt{t
Wjlg d"n Wjlg;Fu} ldl;G5, h;n] ubf{ Wjlg nlDaPsf] ;'lgG5 . Wjlgsf] o;
k|sf/sf] c;/nfO{ u'~hfodfg (Reverberation) elgG5 .
– u'~hfodfgdf bf]xf/] f] cfjfh k|i6 ;'lgbF g} . kf| o xn, ;efux[ , ;flª\ults
sfo{j|md :yn cflb :yfgx¿df s]xL dfq u~' hfodfg x'g] u/L logLx¿sf]
lgdf0{ f ul/Psf] x'G5 . o; Joj:yfn] ;ª\uLtnfO{ lg/Gt/tf kb| fg ub{5 . t/
cfjZostfeGbf a9L u'~hfodfg ePdf ;ª\uLt c:tJo:t xG' 5 . o;
k|sf/sf] c;/af6 d'St xg' xnsf] leTtf / l;lnª Wjlg ;f:] g] j:tn' ]
9flsPsf] x'G5 .

79

lj|mofsnfk 2 k|ltWjlg / u'~hfodfgsf] km/s, kl| tWjlg ;DaGwL ul0ftLo ;d:of

x lel8of] cjnfs] g tyf 5nkmn / k|:tt' ul/Psf] lgisif{sf] cfwf/df k|To]s
ljBfyL{nfO{ k|ltWjlg / u'~hfodfglarsf] km/s rf6{ tof/ kfg{ nufpgx' f];\ .

x k|ltWjlg / u'~hfodfg;Fu ;DaGwL b}lgs hLjgsf 36gfx¿ JofVof ugx'{ f;] \ .

x kl| tWjlg ;DaGwL ;/n ul0ftLo ;d:of xn ug{] ;q" :yflkt ul/lbgx' f];\ .

Wjlgn] kf/ u/]sf] b/L
Wjlgsf] ju] Ö k|ltWjlg ;'lgg nfus] f] ;do

cyjf, V = Or, d =

x Kff7o\ k:' tssf] pbfx/0f 3 jf ;f] h:t} ;d:of lgdf0{ f u/L r/0fa4 ¿kdf
;dfwfg ug'x{ f;] \ / cGo ;d:ofx¿ agfO{ ljBfyLn{ fO{ xn ug{ nufpg'xf];\ .

-u_ dN" ofªs\ g

x Wjlgsf] k/fjt{g, k|ltWjlg / u~' hfodfg egs] f] s] xf] < pbfx/0f;lxt eg .

x k|ltWjlg / u'~hfodfgdf s] s] leGgtf 5g\ <

x gofF aGb} u/]sf 7n' f vfnL sf]7fdf u~' hfodfg x'G5 t/ ;fdfg ePsf]
sf7] fx¿df u'~hfodfg xbF' }g, lsg <

x kfgLhxfhaf6 ;db' |sf] lkFwlt/ k7fPsf] Wjlg t/ª\sf] 2 sec. kl5 kl| tWjlg
;l' gof] eg] ;d'b|sf] ulx/fO slt xf]nf <

-3_ kl/ofh] gf sfo{

ltd|f] l5ds] df /x]sf Wjlgsf ;f| t] x¿sf ;r" L tof/ u/L sIffdf k:| tt' u/ .

lbg 3: ko| f]ufTds ljm| ofsnfk

-s_ ljlzi6 p2]Zo

x kl| tWjlg ;g' /] Wjlgsf] ;f| t] / k/fjtg{ ug]{ j:tl' arsf] b/' L lx;fa ug{

-v_ l;sfO ;xhLs/0f ljm| ofsnfk

x ljBfyLn{ fO{ ljBfno If]q glhs /x]sf] hªu\ n jf kxf8sf] vfr] jf cUnf]
kvf{n ePsf] 7fpdF f 5f6] f] cjnfs] g e|d0fdf nh} fg'xf;] \ .

x e|d0f :yndf k'u]kl5 ;a} ljBfyL{nfO{ kfnk} fnf] kl| tWjlg pTkGg u/fpg
nufpgx' f;] \ / kl| tWjlg ;'lgg nfus] f] ;do :6kjfrsf] ;xfotfn] gf]6 ug{
nufpgx' f];\ . Wjlgsf] ju] (V)= 330m/s dfGg nufpgx' f;] \ .

80

x To;kl5 kT| o]s ljBfyL{nfO{ cfkmn" ] gf]6 u/s] f] ;do / Wjlgsf] ju] k|ofu] u/L
d = ;"qcg;' f/ cfˆgf] / k/fjtg{ ug{] j:t' -;tx_ larsf] b/' L lx;fa ug{

nufpg'xf];\ .
x ;a} ljBfyL{x¿n] lgsfn]sf] b/' Lsf] dfg t'ngf ug{ nufpgx' f];\ .
Gff]6 M ;a} ljBfyL{x¿nfO{ Pp6} 7fFpdf kfnk} fnf] pleP/ s/fpg nufPsf] xg' fn]
kT| o]s ljBfyL{ / k/fjt{g ug{ ;txlarsf] b/' L nueu a/fa/ g} cfpg'k5{ . _
-u_ d"Nofª\sg

x Wjlgsf] ;f| t] / k/fjtg{ ug]{ ;txlar b'/L (d) s;/L kTtf nufOG5 <
x k|ltWjlg eg]sf] s] xf] <
x s] Wjlgsf] ;f| ]t -ltd|f_] k/fjtg{ ug{] j:t'larsf] b/' L 17m eGbf a9L 5 <

olb 17m eGbf sd b/' Laf6 cfjfh lgsfns] f] eP s] xG' Yof] <
-3_ kl/of]hgf sfo{
Ps Ps cf]6f /l] 8of] Ps Ps hgf ljBfyL{sf] ;fydf lnP/ s'g} rf}/sf] kNnf] 5pdf
hfg nufpgx' f;] \ . b'jd} f Pp6} :6];g nufP/ vfN] g nufpgx' f;] \ . Pp6fnfO{ 7'nf]
volume df ahfpg nufpg'xf;] \ . b'j} /l] 8of]af6 cfPsf] cfjfhsf] slt slta]/ kl5
;l' gG5 . Stop watch n] ;dosf] /]s8{ /fVg nufO{ bj' } /]l8of]larsf] b'/L kTtf
nufpg lbgx' f;] \ . o; cj:yfdf kl| tWjlg g;l' gPsfn] d= v/t ko| f]u ug{] eGg'xf];\ .
;Gbe{ ;fdu|L M

1. www.physicsclassroom.com/class/sound
2. www.physicsclassroom.com/media/waves
3. Principles of physics , Grade XI
What is minimum distance for an echo to be produced?

As the sensation of sound persists in our brain for about 0.1 s, to hear a distinct
echo the time interval between the original sound and the reflected one must be at
least 0.1s. If we take the speed of sound to be 344 m/s at a given temperature, say
at 22 ºC in air, sound must go to the obstacle and reach back the ear of the listener
on reflection after 0.1s.

Hence, the total distance covered by the sound from the point of generation to the
reflecting surface and back should be at least (344 m/s) ×0.1 s = 34.4 m. Thus, for
hearing distinct echoes, the minimum distance of the obstacle from the source of
sound must be half of this distance. I.e., 34.4/2=17.2m [given speed of sound
344m/s]

81

82

PsfO 9 rD' asTj (Magnetism)

cg'dflgt 3G6L M 2 -;}4flGts _

1= l;sfO pknlAn

x rD' asTjsf] cf0fljs l;4fGtsf] j0fg{ ug{

x rD' jsLo pkkfbgsf] kl/efiff lbg, k|bzg{ ug{ / j0fg{ ug{

x r'DasLo zlStsf] xf| ;sf] sf/0f / rD' asLo zlSt ;/+ If0fsf pkfox¿
atfpg

2= ljifoj:t' ljefhg / l;sfO ;fduL|

lbg ljifoj:t' l;sfO ;fdu|L

1 rD' asTjsf] cf0fljs l;4fGt 58 rD' asx¿, An8] , r'DasLo j:t' -h:t} M
kmnfdsf] lsnf_, lstfasf] lrq g+= 9.2 /
9.3 k|i6;Fu agfOPsf] sf8{af]8{ k]k/ -
rf6k{ k] /_

2 r'DasLo pkfkfbg, rD' asLo 58 rD' as, kmnfdsf] lsnf, kmnfdsf]
zlStsf] x|f; tyf o;sf] lkgx¿
;/+ If0fsf pkfox¿

3= ljlzi6 p2]Zo, l;sfO ;xhLs/0f lj|mofsnfk / dN" ofªs\ g

lbg 1: r'DasTjsf] cf0fljs l;4fGt (Molecular theory of magnetism)

-s_ ljlzi6 p2]Zo

x rD' assf] kl/efiff lbg
x r'DasLo j:td' f c0f'rD' asx¿sf] l:ylt lrq;lxt atfpg
x r'Dasdf c0f'r'Dasx¿sf] cj:yf lrqåf/f b]vfO{ JofVof ug{
x rD' asTjsf] cf0fljs l;4fGtnfO{ kl/eflift ug{
x c0fr' 'Dassf] kl/efiff lbg
x r'Dassf wa'| x¿ slxNo} klg 5'6l\ 6b}gg\ eGg] tYo k|ofu] åf/f kl' i6 ug{
-v_ l;sfO ;xhLs/0f ljm| ofsnfk

ljm| ofsnfk 1 rD' assf] cjwf/0ff

x sIffdf /xs] f] 6a] n jf ljBfyLx{ ¿sf] 8:] sdf Pp6f 58 r'Das /fVgx' f;] \ /
To;sf] jl/kl/ kmnfdsf 6j' m| f jf lsnfx¿ / afn'jf /fVg'xf];\ .

83

x r'Das glhssf kmnfdsf 6'j|mfx¿ jf lsnfx¿ cfk"mlt/ cfsif0{ f ub{5g\ /
afn'jfnfO{ cfsif0{ f gug]{ s'/f b]vfO{ ljBfyL{x¿nfO{ rD' assf] kl/efiff
atfOlbg'xf];\ .

ljm| ofsnfk 2 c0fr' 'Das tyf cf0fljs l;4fGtsf] cjwf/0ff

x Kff7o\ k':tssf] lrq g+ 9.2 / 9.3 :ki6;Fu agfOPsf] rf6{ kk] / kb| zg{ ug'x{ f;] \
/ o;sf cfwf/df c0f' r'Das, cf0fljs l;4fGtsf] cfwf/df r'DasLo j:t'df
c0f' r'Dasx¿sf] l:ylt af/]df ;f]Rg] hf8] L agfpg] / cg'ej cfbfgk|bfg ug]{
tl/sf ko| fu] ug{'xf];\ .

x KfT| o]s hf]8Laf6 lgisifs{ f] ¿kdf k|:tt' ePsf s/' fx¿nfO{ z}Ifl0fs kf6Ldf
l6Kb} hfgx' f];\ / cGtdf rf6{ k]k/sf] dfWodaf6 yk ki[ 7kf]if0f;lxt lgisif{
lbgx' f;] \ .

ljm| ofsnfk 3 r'Das agfpg] tl/sf / rD' assf wj|' x¿

x ljBfyL{x¿nfO{ kf7o\ k:' tssf] lj|mofsnfk 1 cg';f/ r'Das / An]8sf] ko| fu]
u/L kb| zg{ ugx{' f];\ h;cGtut{ Pp6f An8] lngx' f];\ / To;nfO{ cfwf ugx{' f;] \
/ Pp6f 6'jm| fnfO{ rD' asn] /u8/] rD' as agfpg'xf];\ .

x r'Das ag] gag]sf] ljBfyL{x¿nfO{ k/LIf0f ug{ nufpg'xf];\ .
x An]8sf] pSt 6j' |mfnfO{ ;fjwfgLkj" s{ 4-5 6'j|mf ugx{' f;] \ / kT| os] 6'jm| fdf pTt/L

/ blIf0fL w|'j 5g\ eGg] olsg ug{ r'DasLo sDkf;sf] ;xfotf lngx' f;] \ . oL
6'jm| f / afFsL cfwfsf] 6'jm| flar s] cGt/ x'G5 < 6j' m| fx¿df lrxg\ nufO{ ;Fu}
s;/L a:5g\ < cjnfs] g ug{ nufO{ lgisif{ eGg nufpg'xf];\ .
x Dfflysf] lj|mofsnfknfO{ k|Tos] 8:] s jf aG] rut ¿kdf ljBfyL{x¿nfO{ ug{
nufpg'xf;] \ / o; sfo{df ;xhLs/0f ug'{xf;] \ .
-u_ d"Nofªs\ g
x rD' assf] cf0fljs l;4fGt eg]sf] s] xf] <
x c0fr' D' as eg]sf] s] xf] <
x rD' asLo j:t' / rD' asdf c0f'rD' asx¿sf] l:ylt lrqåf/f b]vfpm .
x rD' asn] r'DasLo u0' f bv] fp5F t/ r'DasLo j:t'n] b]vfpFbg} , lsg <
x r'DasnfO{ hlt 6j' |mf kf/] klg o;sf w|'jx¿nfO{ 5'6\ofpg ;lsFb}g, lsg <
-3_ kl/of]hgf sfo{
ljBfyL{x¿nfO{ j:t' / rD' asdf c0fx' ¿sf] l:ylt sf8a{ f8] {df lrq agfO{ sIffdf k|bz{g
ug{ nufpg'xf];\ .

84

-ª_ k|fljlws zAbfjnL
c0f' r'Das M ;a}eGbf ;fgf] 6j' m| f h;df rD' asLo u'0f ljBdfg xG' 5 .
rD' asLo j:t'M hg' j:tn' fO{ r'Dasn] tfG5 .
-r_ lzIfssf nflu yk k[i7kfi] f0f
k[YjL cfkm}F klg 7n' f] rD' as xf] . o;sf] ef}uf]lns pTt/L w'|jk6\l6 r'DasLo blIf0fL w|'j
k5{ . To:t} o;sf] ef}ufl] ns blIf0fL w'|ak6l\ 6 rD' asLo pTt/L w|'a k5{ . kY[ jLsf]
;txdf :jtGq ¿kdf em'G8fOPsf] 58 rD' assf] pTt/L w|j' nfO{ k[YjLsf] rD' asLo
blIf0fL w'|jn] cfsif0{ f ug{] xFb' f ha emG' 8fOPsf] r'Das l:y/ cj:yfdf cfpF5, o;sf]
pTt/L wj'| kY[ jLsf] rD' asLo blIf0fL cyf{t\ ef}uf]lns pTt/L w'|jlt/ kmls{G5 .
Magnetic compass klg pTt/ blIf0f kmlsg{ 'sf] sf/0f oxL xf] . t/ o;n] l7s
efu} fl] ns pTt/ jf blIf0f w'|j b]vfpg ;Sb}g lsgls k[YjLsf] efu} f]lns pTt/ /
rD' asLo blIf0f wj'| x¿ Pp6} laGbd' f kb}{gg\ .

lbg 2: r'DasLo pkkfbg, r'DasLo zlStsf] x|f; tyf o;sf] ;/+ If0fsf
pkfox¿

-s_ ljlzi6 p2]Zo
x rD' asLo pkkfbgsf] kl/efiff lbO{ k|ofu] åf/f kb| zg{ ug{
x r'DasLo zlStsf] x|f;sf] kl/efiff lbO{ o;sf] sf/0f atfpg
x r'DasLo zlSt ;+/If0f ug{] pkfox¿ pNnv] ug{

-v_ l;sfO ;xhLs/0f lj|mofsnfk
lj|mofsnfk 1 r'DasLo pkkfbgsf] cjwf/0ff

x sIffsf] cfsf/ / ljBfyL{ ;ªV\ ofcg';f/ ;dfj]lztfsf] cfwf/df ljBfyL{x¿sf]
;dx" lgdf{0f ug'{xf];\ .

x k|To]s ;dx" nfO{ 58 rD' as, kmnfdsf] lsnf / lkgx¿ ljt/0f ug'{xf];\ .
kT| o]s ;dx" nfO{ lstfasf] ljm| ofsnfk …2Ú df eg] cg;' f/ k|ofu] ug{ nufO{
5nkmn u/fpgx' f;] \ / lgisif{ eGg nufpgx' f];\ .

x ljBfyL{sf] ;d"xaf6 lgisif{ kf| Kt ePkl5 yk JofVof ub}{ ;?' df kmnfdsf]
lsnfn] lkgnfO{ cfslif{t ug{ g;Sg' t/ kl5 cfslift{ ug{ ;Sg' rD' assf]
ke| fjn] kmnfdsf] lsnfdf rD' asLo pkkfbg (magnetic induction) ePsfn]
xf] eGg] tYo ki| 6 kfl/lbgx' f];\ .

x r'DasLo pkkfbg cjwf/0ffsf] af/]df dl:tis e~emf ljlwsf] k|of]u ub}{
r'Dasåf/f s;/L rD' asLo j:td' f r'DasLo pkkfbg x'G5 eGg] s/' fsf] k:| t't
ug{ nufpg'xf;] \ .

85

x r'DasLo pkkfbg ljm| ofnfO{ yk k|i6 kfg{ kf7\ok':tssf] kh] g=+ 83 sf]
k|of]ufTds sfo{ -1_ sf] ko| f]u u/L kb| z{g ugx'{ f;] \ .

o;sf nflu Pp6f rD' as, sDkf; / kmnfdsf] lsnf lng'xf];\ .
lsnfnfO{ 6]andf /fVg'xf];\ / s'g} ljBfyL{nfO{ lsnfsf] glhs} r'Dassf]

pTt/L wj|' nh} fg eGgx' f];\ .
ca sDkf;sf] ;xfotfn] lsnfsf] csf{] 5]p sg' w|j' aGof] < kTtf nufpg

eGg'xf;] \ .
oxL k|lj|mof rD' assf] blIf0fL w|j' lsnf glhs NofP/ bf]xf]/fpg nufpgx' f;] \ .
r'DasLo pkkfbg xb'F f r'Dassf] pTt/ w'|j glhssf] 5]pdf blIf0f w|'j / blIf0f wj|'
glhssf] 5p] df pTt/ w|j ljsl;t x'g] s'/f sDkf;sf] ;xfotfn] :ki6 agfOlbgx' f;] \ .
ljm| ofsnfk 2 r'DasLo zlStsf] xf| ; / ;+/If0fsf pkfox¿
x rD' asLo zlStsf] x|f; ljifodf ;fR] g nufpg'xf];\ / JolStut ¿kdf k:| tt' ug{
nufpg'xf];\ .
x ljBfyLa{ f6 cfPsf s/' fx¿nfO{ ;d]6L r'DasLo zlStsf] x|f; ;DaGwdf Pp6f 58
r'Das lnP/ xf| ; xg' ] sf/0fx¿nfO{ kb| zg{ ug'{xf];\ .
x cGTodf rD' asLo zlSt s;/L ;/+ If0f ug{ ;lsG5 egL 5nkmn u/fpg'xf];\ /
5nkmnkl5 aF'bfut ¿kdf rD' asLo zlSt hf]ufO{ /fVg] pkfox¿nfO{ ljBfyL{x¿n]
k|:t't u/s] f cge' jx¿nfO{ ;d6] L z}Ifl0fs kf6Ldf tof/ ug'x{ f];\ .
-u_ dN" ofªs\ g
x r'DasLo pkkfbg eGgfn] s] al' emG5 <
x rD' asLo pkkfbg xF'bf r'DasLo j:td' f w'|jx¿ s;/L ljsl;t xG' 5g\ <
x rD' asLo pkkfbgnfO{ Pp6f ko| fu] fTds ljm| ofsnfk u/L kl' i6 u/ .
x r'DasLo zlStsf] xf| ; eg]sf] s] xf] < o;sf sf/0f s] s] xf]nfg\ <
x r'Dassf] rD' asLo u'0f x|f; u/fpg] s'g} ltg cf]6f ljm| ofsnfk eg .
x r'DasLo pkkfbg / rD' asLo xf| ;sf leGgtf k:| t't u/ .
x r'DasLo zlSt ;/+ If0f ug{] ltg cf6] f pkfox¿ s] s] xg' ;S5g\ <
-3_ k|fljlws zAbfjnL

sDkf; M pTt/ / blIf0f lbzf kTtf nufpg ko| fu] ul/g] pks/0f
rD' assf] cIf (Axis of Magnet) : r'Dassf] bO' c{ f]6f w|j' x¿ hf8] \g] /]vf
rD' asLo dWo/]vf (Equatorial line) : rD' assf] cIf;Fu nDa bO' {cf]6f dWoljGb'af6
hfg] /v] f
-ª_ kl/ofh] gf sfo{
kmnfdsf] lsnf, rD' as, tfdfsf] tf/sf] ko| fu] u/L ljBt' \ rD' as agfO{ k/LIf0f u/L
lrq ;lxt sIffdf k|:t't u/

86

PsfO 10 ljB't\ (Electricity)

cg'dflgt 3G6L M 5 (4 ;4} flGts_ ± 1 k|ofu] fTds_

1= l;sfO pknlAw

x ;fwf/0f ;]n / 8«fO ;n] sf] ;fdfGo agf]6 / pkof]lutf j0f{g / kb| z{g ug{

x ufx:{ y ljBt' Ls/0f tyf o;sf pks/0fx¿sf] kl/ro lbg

x ˆmo\ h' / Pd=;L=aL= sf] kl/ro / o;sf] ko| f]u atfpg
2= ljifoj:t' ljefhg / l;sfO ;fdu|L

lbg ljifoj:t' l;sfO ;fdu|L

1 ;fwf/0f ;n] sf] kl/ro, o;sf ;fwf/0f ;n] hl8t lrq -las/, tfdf /
ql' 6x¿ / pkofl] utf h:tfsf] kftf, aNa, tf/, ;Nkm\ol' /s cDn_

2 zi' s ;]nsf] kl/ro / pkofl] utf z'is ;n] (Dry cell)

3 ko| f]ufTds ljm| ofsnfk las/, kfgL, ;Nkmo\ l' /s cDn, tfdfsf] kftf,

h:tfsf] kftf, 6rs{ f] ln8 aNa, ;r' fns
tf/, zi' s ;]n

4 Uffx:{ y ljBt' Ls/0f / s]xL House wiring system sf] gdg' f bv] fOPsf]

ufx{:y ljB't\ pks/0f rf6,{ ;Dej eP sx] L pks/0fx¿

5 k\moh' / Pd= ;L= aL= Kfm\oh' sf] gd'gf

3= ljlzi6 p2]Zo, l;sfO ;xhLs/0f ljm| ofsnfk / d"Nofªs\ g

lbg M 1 ;fwf/0f ;n] sf] kl/ro, o;sf q'l6x¿ / pkof]lutf

-s_ ljlzi6 p2]Zo

x ;fwf/0f ;]nsf] kl/ro atfpg / gfdfª\lst lrq agfpg

x ;fwf/0f ;n] sf] q'l6sf] JofVof u/L q'l6x¿ x6fpg] pkfo eGg

x ;fwf/0f ;n] sf] pkof]lutf atfpg

-v_ l;sfO ;xhLs/0f lj|mofsnfk
lj|mofsnfk 1 ;fwf/0f ;n] sf] kl/ro / q'l6x¿

x ;fwf/0f ;]nsf] lrq k|bz{g u/L To;df h8fg ul/Psf ;fduL| x¿sf] gfd

atfpg nufpgx' f];\ .

x Gffd klxrfg u/s] f] cfwf/df ;fwf/0f ;n] sf] kl/ro lbg nufpgx' f];\ .

x ;fwf/0f ;]nsf] agfj6sf] cfwf/df o;sf ql' 6x¿df 5nkmn u/fpgx' f];\ .

x ljBfyL{x¿n] 5nkmn4f/f k|:t't u/]sf cfwf/df ;fwf/0f ;]nsf ql' 6x¿

w|j' Ls/0f / :yfgLo lj|mofsf] af/d] f atfpg'xf;] \ . o;sf] nflu oL b'O{
ql' 6x¿sf] ;DaGwdf cem wf/0ff k|i6 kfg{ >JobZ[ o ;fdu|L k:| t't ug{'xf];\ .

x ;fwf/0f ;n] sf q'l6 cGtu{t :yfgLo lj|mofnfO{ /fs] yfd ug{] pkfo s] xfn] f

eGg] ;DaGwdf ;f]Rg] hf8] L agfpg] / cge' j cfbfgk|bfg ug]{ tl/sf k|of]u
ugx{' f;] \ / lgisif{ k:| t't ugx'{ f;] \ .

87

lgisif{ M :yfgLo ljm| ofsf] /fs] yfd ug{] pkfodf z'4 h:tfsf] kftfsf] ko| fu]
ug{] jf h:tfsf] kftfnfO{ aflx/af6 kf/fn] ] nk] g ug{k' 5{ .

x ;fwf/0f ;n] n] w]/} a/] ;Dd ljB't\ pTkfbg ug{ g;Sg] s/' f :d/0f u/fpbF }
o;sf] pkof]u ubf{ x'g] cK7/] fx¿ -;d:of_ af/] 5nkmn u/fO{ lgisif{
atfOlbg'xf;] \ .

lj|mofsnfk 2 ;fwf/0f ;n] sf] pkfofl] utf

x ;fwf/0f ;]nsf] pkof]lutf ;DaGwL lel8of] k|bz{g ugx{' f];\ / cjnf]sg ug{
nufpgx' f];\ jf ;fwf/0f ;]nsf] pkof]lutf ;DaGwdf dl:tis em~hf ljlwsf]
ko| f]u u/L k:| tt' ug{ nufpgx' f;] \ .

x ljBfyL{x¿n] k|:t't u/s] f cg'ejx¿nfO{ ;d6] L lgisif{ lbg'xf;] \ .
lgisif{ M sd dfqfdf ljBt' cfjZostf kbf{ ;lhn;} Fu lgdf0{ f / ko| f]u ug{
;fwf/0f ;]nsf] k|of]u ug{ ;lsG5 .

-u_ d"Nofªs\ g

x ;fwf/0f ;]nsf] gfdfl+ st lrq agfpm .

x ;fwf/0f ;n] sf q'l6x¿ s] s] x'g\ <

x ;fwf/0f ;n] df w'|jLs/0f eg]sf] s] xf] < of] s;/L x6fpg ;lsG5 <

x :yfgLo ljm| of eGgfn] s] a'lemG5 < of] ljm| of /f]Sg] pkfo s] xf] <

x ;fwf/0f ;n] sf] pkof]lutf s] s] xg' \ < o;sf] pkof]u ug{ s] s] cK7o\ f/fx¿
5g\ <

-3_ kl/of]hgf sfo{
Rff6{ k]k/df ;kmf, :ki6 / gfdfª\lst ;fwf/0f ;]nsf] lrq agfpg nufpgx' f;] \ .
-ª_ kl| jlws zAbfjnL
-r_ lzIfssf nflu yk k[i7kfi] f0f
lkmsf ;Nˆo'l/s cDn (dil.sulphuric acid) tof/ ubf{ Wofg lbgk' g]{ s'/f M

x lkmsf ;Nˆol' /s cDn tof/ ubf{ s8f ;Nkmo\ l' /s cDndf slxNo} kfgL
vGofpg' xb'F }g . o;f] ubf{ /f;folgs k|ltlj|mof eO{ tft/] k8\lsg] / b3' 6{ gf x'g]

8/ x'G5 . hlxn] klg kfgLdf s8f cDn lj:tf/} yfk] f yf]kf u/L vGofpgk' 5{ .
;fwf/0f ;]ndf xg' ] /f;folgs k|ltljm| of
;fwf/0f ;]naf6 ljBt' \ pTkfbg ug]{ k|ljm| of klg Ps lsl;dsf] cfof]gLs/0f k|ljm| of xf]
. o;df lkmSsf ;Nˆol' /s cDn (H2SO4) n] On]S6f« ]nfO6, tfdfsf] kftfn] Pgf8] /

h:tfsf] kftfn] Sofyf]8sf] sfd u5{ / /f;folgs kl| tlj|mof o;ks| f/ xG' 5 M
2H+ + SO4- -
H2SO4

tfdfsf] kftfdf -Pgf]8df_ h:tfsf] kftfdf -Sofyf]8df_
2H+ 2H +2e- SO4- - + Zn ZnSO4 + 2e-

H2

88

lbg M 2 z'is ;n] (Dry cell) sf] kl/ro / pkof]lutf

-s_ ljlzi6 p2]Zo

x z'is ;n] (Dry cell) sf] kl/ro lbg / gfdfª\lst lrq agfpg

x zi' s ;]nsf] agfj6 JofVof ug{

x z'is ;]nsf] pkof]lutf / q'l6 atfpg

x ;fwf/0f ;]n / z'is ;n] lar leGgtf atfpg

-v_ l;sfO ;xhLs/0f lj|mofsnfk
ljm| ofsnfk 1 zi' s ;n] sf] kl/ro

x ;jk{ |yd ljBfyLx{ ¿nfO{ zi' s ;]n kb| zg{ ug{'xf;] \ .

x z'is ;n] / ;r' fns tf/ k|ofu] u/L 6r{nfO6sf] ln8 aNa afn]/ kb| z{g
ugx{' f];\ .

x kb| zg{ ul/Psf] cfwf/df zi' s ;n] sf] kl/ro lbg nufpg'xf];\ .
ljm| ofsnfk 2 z'is ;n] sf] agf]6

x ljBfyL{x¿nfO{ cfjZos ;dx" df -;dfj]zL ;d"x_ ljefhg ugx{' f];\ / k|ofu]

eO;ss] f] z'is ;n] nfO{ ;d"xut ¿kdf ljt/0f ug'{xf];\ .

x zi' s ;]nsf ;a} efux¿ -leq / aflx/_ sf] cjnf]sg ug{ nufpg'xf;] \ /

kT| os] efusf] sfo{df 5nkmn ug{ nufpgx' f;] \ .

x kf7\ok':tssf] lrq g+= 10.2 cg;' f/ Dry Cell sf] lrq k|bzg{ ug{x' f];\ /

ljBfyL{nfO{ klg o;sf] gfdfª\lst lrq lvRg nufpgx' f;] \ .

x To;kl5 lrqcg';f/ zi' s ;n] sf] agfj6sf] JofVof ug{ nufpgx' f;] \ / oxL

jm| ddf h:tfsf] eFf8fn] C0fw|j' / sfag{ /8n] wgw'j| sf] sfd u5{ eGg] tYo
:ki6 u/fO{lbgx' f];\ .

x bl[ i6ljxLg ljBfyL{x¿nfO{ z'is ;n] / o;leqsf efux¿sf] :kz{ u/fpg'xf;] \

eg] alx/f ljBfyL{x¿sf] nflu JofVofTds ljlw ckgfpg'xf];\ .
ljm| ofsnfk 3 zi' s ;n] sf] pkof]lutf

x lj|mofsnfk Psdf kb| z{g ul/Pcg';f/sf] kIfdf a]Gr jf 6]an' ut ¿kdf
5nkmn ug{ nufO{ z'is ;n] sf] pkofl] utfdf 5nkmn ug{ nufpg'xf;] \ .

x kT| os] a~] raf6 Ps pkof]lutf eGg nufO{ zI} fl0fs kf6Ldf l6Kg'xf];\ . l6k]sf
s'/fdf 5nkmn u/fO{ zi' s ;]nsf pkofl] utfx¿af/] yk ki| 6 kfl/lbgx' f;] \ .

x dfly plNnlvt lbg Ps / lbg bO' {sf lj|mofsnfkx¿sf] cfwf/df ;fwf/0f
;]n / zi' s ;]ndf s] s] km/s /x]5g\, 5nkmn ug{ nufO{ k:| t't ug{
nufpgx' f];\ .

89

x ljBfyL{x¿n] k:| t't u/s] f kIfx¿nfO{ ;d]6b\ } zi' s ;]ndf DofGulgh
8fOcS;fO8 (MnO2) /flvPsfn] ] w'a| Ls/0f gx'g] t/ :yfgLo ljm| of gfds ql' 6
xg' ] s'/f ;d]t :ki6 ul/lbg'xf];\ .
-u_ dN" ofªs\ g

x z'is ;]n egs] f] s] xf] < of] s;/L ags] f] x'G5 <

x zi' s;n] sf] ;kmf / gfdfª\lst lrq tof/ u/ .

x Dry Cell df wgwj'| / C0fw|j' sf] sfd s] s]n] u5{g\ <

x 8f« O ;n] s] sfdsf] nflu k|ofu] ul/G5 <

x z'is ;n] df w'j| Ls/0fsf] ;d:of xF'bg} , lsg <

x ;fwf/0f ;]nsf] tn' gfdf z'is ;]nsf] k|ofu] ;lhnf] / w]/} xG' 5, lsg <

-3_ kl/of]hgf sfo{
ljBfyL{x¿nfO{ b}lgs hLjgdf 6r{nfO6, /]l8of], l/df]6, 38L, vn] f}gf cflbdf ko| f]u
ul/g] zi' s ;n] x¿ ;ª\sng ug{ nufO{ cjnf]sg ug{ nufpgx' f;] \ . cjnf]sgkZrft\

ltgLx¿sf] ;fOh, cfsf/ / ef]N6h] t'ngf ug{ eGg'xf];\ / k|ltjb] g agfO{ sIffdf
k:| tt' ug{ nufpgx' f];\ .
-ª_ k|fljlws zAbfjnL M
Mangaese Dioxide (Mno2) M Ps lsl;dsf] /;fog h'g Dry cell df polarization

x6fpg k|ofu] ul/G5
Pdf]lgod Snf]/fO8 (NH4Cl) M Dry Cell df Electrolyte sf ¿kdf k|ofu] ul/Psf]

/;fog
-r_ lzIfssf nflu yk k[i7kfi] f0f
;fwf/0f ;n] / 8«fO;n] lar leGgtf

;fwf/0f ;]n 8f« O{ ;]n

1. o;df lkmSsf ;Nˆo'l/s cDn -t/n_ 1= o;df t/n kbfys{ f] ko| f]u x'Fbg} .
sf] ko| f]u xG' 5 .

2. o;df wgw'j| sf] sfd tfdfsf] kftfn] 2= o;df C0fwj'| sf] sfd h:tfsf]
/ C0fwj'| sf] sfd h:tfsf] kftfn] u5{ . eFf8fn] u/] klg wgw'|jsf] sfd sfag{
/8n] u5{ .

3. o;df wj|' Ls/0f / :yfgLo lj|mof 3= o;df :yfgLo lj|mof q'l6 eP klg
gfds bO' {cf6] f q6' L x'G5g\ h;n] ubf{ wa|' Ls/0f gxg' ] x'gfn] w]/} a/] ;Dd
w/] } a/] ;Dd ljB't\ pTkfbg ug{ ;lsbg} . ljB't\ pTkfbg ug{ ;lsG5 .

4. o;nfO{ otfptf n}hfg cK7]/f] k5{ . 4= o;nfO{ ;lhn} otfptf n}hfg
;lsG5 .

5. o;df OnS] 6«f]nfO6sf] ¿kdf lkmsf 5= o;df On]S6f« ]nfO6sf] ¿kdf

;Nˆo'l/s cDnn] (dil. H2So4) sfd u5{ . Pdf]lgod Snf]/fO8 (NH4Cl) n] sfd
u5{ .

90

lbg M 3 k|ofu] fTds ljm| ofsnfk

-s_ ljlzi6 p2]Zo

x k|ofu] zfnfdf ;fwf/0f ;]n tof/ ug{

x ;fwf/0f ;n] sf] lrq agfpg

-v_ l;sfO ;xhLs/0f ljm| ofsnfk

x ;j{k|yd ljBfyL{x¿nfO{ -sIff jf ko| f]uzfnf_ ljBfyL{ ;ª\Vof / pknAw
;fdu|Lsf] cfwf/df pkoS' t ;dx" df ljefhg ug'{xf;] \ .

x To;kl5 kT| o]s ;dx" nfO{ lkmsf ;Nˆo'l/s cDn agfpg] tl/sf lzIfs :jo+n]
k|bz{g ugx'{ f];\ / lj|mofsnfk 1 sf] ;dx" nfO{ las/df lkmsf ;Nˆol' /s cDn
tof/ ug{ nufpg'xf;] \ . o;sf nflu k|Tos] ;dx" df Ps Ps cf6] f las/df
100 ml kfgL /fVg nufpg] / To;df ;fjwfgLk"js{ 10 ml hlt Sulphuric
acid sf] yfk] f r'xfpg nufpgx' f];\ .

x To;kl5 las/df ePsf] lkmsf cDndf Pp6f tfdfsf] kftf / csf]{ h:tfsf]
kftf 8'afpg nufpgx' f;] \ / tL kftfx¿nfO{ ;'rfns tf/n] Pp6f ;fgf] 6r{sf]
ln8 aNa;uF kf7\ok':tssf] lrq g=+ 10.1 df bv] fP h:t} u/L hf8] g\
nufpgx' f];\ / ;fwf/0f ;]n tof/ ePsf] s'/f elglbgx' f];\ .

x aTtL aN5 ls aNbg} < slt a]/;Dd aN5 < aQL aln/xbF f las/df s]
bl] vG5 < cjnf]sg ug{ nufpg'xf;] \ . k|Tos] ;d"xnfO{ lzIfsn] ;xhLs/0f ub{}
;fwf/0f ;n] n] s;/L sfd u5{ < JofVof ug{ nufpgx' f;] \ / ;xhLs/0f ug'{xf;] \
.

-u_ d"Nofªs\ g

x ;fwf/0f ;n] df /f;folgs k|ltlj|mof eO{ aTtL aln/xbF f tfdfsf] kftfdf
s:tf] bl] vG5 < tfdfsf] kftfdf hDdf xg' ] UoFf; sg' xf] <

x ;fwf/0f ;]ndf wgw'j| / C0fw'|jsf] sfd s] s]n] ub{5g\ <

x aNa cToGt} yf/] } ;do;Dd dfq aNgs' f] sf/0f s] xf]nf <

x ;fwf/0f ;]ndf bv] fkg{] ql' 6x¿ s] s] xg' \ <

x ;fwf/0f ;]ndf bv] f kg{] q'l6x¿ lg/fs/0f ug{ s] ug{'k5{ <

x ;fwf/0f ;]n s:tf] cj:yfdf a9L pkofu] L x'G5 <

x ;fwf/0f ;]nsf] sdhf]/L s] xf] <

91

-3_ kl/ofh] gf sfo{

;fwf/0f ;n] agfpg nufO{ k|bz{g ug{ nufpg] jf Pp6f rf6{ k]k/df Dry cell /
Simple cell sf] ;kmf lrq agfO{ logLx¿larsf] leGgtf b]vfpg nufpg]

-ª_ kf| ljlws zAbfjnL

;'rfns tf/M ljB't\ k|jfx ug{] tf/

lbg M 4 ufx:{ y ljB'tLs/0f / sx] L ufx{:y ljB't\ pks/0fx¿

-s_ ljlzi6 p2]Zo

x ufx{:y ljB'tLs/0fsf] kl/ro lbO{ JofVof ug{

x ufx:{ y ljB't\ pks/0fsf] kl/ro lbO{ bl} gs hLjgdf k|of]u x'g] sx] L
pks/0fx¿sf] gfd / ljzi] ftf atfpg

-v_ l;sfO ;xhLs/0f ljm| ofsnfk

lj|mofsnfk 1 ufx{:y ljBt' Ls/0fsf] kl/ro

x ljBfyL{x¿nfO{ cfˆgf] 3/df ePsf] Wiring system sf] af/]df cfˆ"mn]
hfg]sf, bv] s] f s/' fx¿ eGg nufpg'xf];\ .

x To;}u/L ljBfnodf ul/Psf] ljBt' \ h8fg sfos{ f] ;d]t cjnfs] g ug{
nufpgx' f];\ .

x House Wiring system sf] gdg' f bv] fOPsf] rf6{ sIffsf]7fdf kb| z{g ub}{
ufx{:y ljB'tLs/0f (House wiring system) sf] af/]df k|i6;uF JofVof
ul/lbg'xf];\ .

x ljB't\ ux[ af6 pTkfbg ul/Psf] ljBt' \ s;/L 3/3/df /x]sf ljB't\
pks/0f;Dd k'¥ofOG5 < eGg] s/' f :ki6 kfl/lbgx' f];\ . tTkZrft\ ufx{:y
ljB'tLs/0fnfO{ kl/eflift ul/lbg'xf;] \ .

ljm| ofsnfk 2 ljB't\ vkt ug{] pks/0fx¿

x ljBfyL{x¿nfO{ ljB't\ vkt ug{] pks/0fx¿sf] gfd ;fW] gx' f];\ / z}Ifl0fs
kf6Ldf l6kf6] ugx'{ f];\ .

x Uffx{:y ljB't\ pks/0fsf] kl/ro lbg nufpg'xf];\ . sx] L pks/0fx¿ h:t} M
ljBt' Lo aTtL, lx6/, ljB't\ 3G6L, /l] 8of], 6]lnlehg, 6l] nkmf]g÷df]afOn,

92

sDKo'6/ cflbsf] kl/ro tyf ljzi] ftfx¿ JofVof ul/lbg'xf;] \ . -;Dej eP;Dd
pks/0fx¿ kb| z{g klg ugx{' f];\ ._

x ljB't\ pks/0fx¿ ;DaGwL >JobZ[ o lel8of] kb| zg{ u/L yk ki[ 7kfi] f0f k|bfg
ug'{xf];\ .

-u_ d"Nofª\sg

x ufx{:y ljB'tLs/0f egs] f] s] xf] < of] s;/L ul/G5, j0fg{ u/ .

x ufx:{ y ljB'tLs/0fdf pks/0fx¿nfO{ s'g ¿kdf h8fg ul/G5 < -;dfgfGt/
¿kdf jf ;dfgfGt/ kl/ky_

x ˆo'hnfO{ ;wF } nfOe tf/df hf8] g\ k' 5{, lsg <

x ufx:{ y ljBt' \ pks/0f eg]sf] s] xf] < s'g} 4 cf]6f pks/0fsf] gfd n]Vf .

x 5f6] f] l6Kk0fL n]v . ii_ ljB't\ 3G6L
i_ ljB'tLo aTtL

x ltdf| ] 3/df ko| f]u ul/g] ljB't\ pks/0fx¿ s] s] x'g\, gfd eg .

-3_ kl/of]hgf sfo{

ljBfyL{x¿nfO{ ljBfno Ifq] jf pgLx¿sf] 3/ j/k/ ev/{ } lgdf0{ f ePsf 3/ jf
ejgdf eO/xs] f] ufx{:y ljB'tLs/0f sfo{ cjnf]sg ug{ nh} fg'xf];\ . To;kl5
Onl] S6l« ;og;Fu Wiring system ;DaGwL k|Zg jf lh1f;fx¿ /fVg nufpgx' f;] \ .

jf Bulb / Tube light afxs] ltdf| ] 3/df sg' sg' ljB'tLo ;fdfg 5g\, ltgLx¿n]
slt slt watt ljB't\ vkt u5{g eGg] ;"rgf;lxt Pp6f tflnsf tof/ kf/ .

-ª_ kf| ljlws zAbfjnL

l:jr M ljB't\ kl/ky aGb ug{ / vf]Ng k|ofu] ul/g] pks/0f

d'Vo l:jr M 3/df lelqg] k'/} ljBt' n\ fO{ lgoGq0f ug]{ :jLr

ljB't\ nf8] M ljBt' \ vkt ug]{ pks/0fx¿

lbg M 5 k\mo'h / Pdl;aL -MCB)

-s_ ljlzi6 p2]Zo

x k\mo'hsf] kl/ro lbg / o;sf] k|of]u tyf dxTTTj atfpg

x MCB sf] kl/ro / ko| f]u tyf dxTTTj atfpg

x ˆo'h / Pd= ;L= aL= lar km/s 56' \ofpg

93

v_ l;sfO ;xhLs/0f ljm| ofsnfk

lj|mofsnfk 1 km\oh' sf] kl/ro, agfj6 / pkofl] utf

x ljBfyL{nfO{ kf7\ok':tssf] lrq g=+ 10.4 cjnf]sg ug{ nufpg'xf;] \ .

x To;kl5 sIffdf ˆoh' sf] gd'gf kb| z{g ug'{xf;] \ / cjnfs] g ug{ nufpg'xf;] \ .
x Kfmo\ 'hsf] agf6] , k|ofu] ug{] tl/sf / pkof]lutf ;DaGwL >JobZ[ o ;fdu|L

k:| tt' ug'{xf];\ / ljBfyL{x¿nfO{ cjnf]sg ug{ nufO{ dV' o dV' o aF'bfx¿ l6kf]6
ug{ nufpg'xf;] \ .
x ljBfyL{x¿nfO{ a]Grut jf 6a] n' ut ¿kdf kmo\ h' sf] kl/ro, agf6] , sfo{
kl| jm| of / pkofl] utf ;DaGwdf 5nkmn ug{ nufO{ k:| t't ug{ nufpgx' f;] \ .
x ljBfyL{x¿n] k|:tt' u/]sf cge' jx¿nfO{ ;d]6b\ } km\o'hsf] kl/ro, agf]6, sfo{
kl| j|mof / pkfofl] utf ;DaGwdf lgisif{ lbg'xf;] \ .

lj|mofsnfk 2 Pd=;L=aL sf] kl/ro, agfj6 / pkof]lutf

x kf7\ok:' tssf] lrq g=+ 10.5 cjnf]sg ug{ nufO{ MCB sf] k"/f ¿k atfpg
nufpgx' f];\ . k"/f ?k M Miniature Circuit Breaker egL atfOlbg'xf;] \ .

x Pd=;L=aL= sf] kl/ro, sfo{ kl| j|mof / pkof]lutf ;DaGw >Job[Zo ;fdu|L
kb| zg{ ug{x' f;] \ / ljBfyLn{ fO{ cjnfs] g ug{ nufpgx' f];\ .

x tTkZrft\ MCB k|bz{g ug{'xf;] \ . cjnf]sg ul/Psf] >Jo bZ[ o ;fdu|L /
kb| zg{ ul/Psf] Pd=;L=aL=sf] cjnfs] gsf] cfwf/df Pd=;L=aL=sf] kl/ro,
agf]6 / pkof]lutfaf/d] f k:| tt' ug{ nufpg'xf];\ / lgisif{ lbg'xf];\ .

x dfly 5nkmn ul/Psf b'O{ cf6] f k\moh' / Pd= ;L= aL= km\o'hsf] cfwf/df
leGgtf tof/ ug{ nufpg'xf;] \ . rf6{ agfpg] sfo{df ;xhLs/0f ugx'{ f;] \ /
lgDg lgisif{ lbg'xf;] \ .

k\mo'h MCB

1. cfk\mgf] IfdtfeGbf a9L ljB't\ k|jfx 1. of] km\ o'hsf] ljsl;t ¿k xf,] h;n]

ePdf :jtM kUn/] kl/kydf ljB't\ kj| fx kl/kydf cfjZostfeGbf a9L ljB't\
/f]Sg k|ofu] ul/g] dl;gf] tf/sf] 6j' |mfnfO{ k|jfx ePdf :jtM l:jr aGb u/L ljB't\
km\ oh' elgG5 . k|jfxnfO{ /fS] 5 .

2. k\moh' tf/ kUnd] f tf/ k]m/]/ k|ofu] df 2. MCB df tf/ km] g'{ kb{}g . l:jr cg

NofOG5 . ugf;{ fy o;n] km] l/ sfd ug{ ;'? u5{ .

-u_ d"Nofªs\ g

x km\ oh' eg]sf] s] xf] < o;n] kl/kydf s;/L sfd ub5{ <
x k\mo'hsf] s] dxTTTj 5 <

94

x kl/kydf axg] ljB't\ wf/f;uF a/fa/ jf To;eGbf sd Ifdtfsf] k\moh' ko| fu]
u/]df s] x'G5 <

x MCB egs] f] s] xf] < o;n] s;/L sfo{ ub5{ < of] s'g l;4fGtdf cfwfl/t xG' 5
<

x ˆoh' / Pd= ;L= aL= lar s] km/s 5 <
-3_ kl/of]hgf sfo{

ljBfyL{x¿nfO{ cfcfˆgf] 3/df ko| fu] ePsf ˆoh' / Pd= ;L= aL= sf] cjnf]sg u/L
ˆoh' / MCB n] s;/L sfd ub5{ g\ < lrq agfpg nufO{ o;n] ug]{ sfo{ k|ljm| of k:| tt'
ug{ nufpg'xf];\ .

-ª_ yk cWoog ;fduL|

x kY[ jLsf] kf]6l] G;on km/s (P.D.) eGbf a9L kf6] ]lG;on km/s xg' ] tf/nfO{ nfOe
tf/ elgG5 .

x k[YjLsf] kf]6l] G;on km/s;Fu a/fa/ kf6] l] G;on km/s xg' ] tf/nfO{ t6:y tf/
elgG5 .

tf/ Tff/sf] aflx/L sr' fnssf] /ª

nfOe (Phase) /ftf] jf v}/f]

t6:y (Neutral) sfnf] jf lgnf]

k[YjL ( Earth) xl/of] jf kxn] f]

ufx:{ y ljB'tLs/0fsf] gdg" f lrq

95

kmo\ 'h 5gf]6 ubf{ Wofg lbg'kg{] s/' fx¿
;ae} Gbf klxn] 3/df k|ofu] ePsf ;Dk0" f{ pks/0fsf] Power hf8] \gx' f];\ .
xfdf| ] b]zsf Home supply df Volt sf] dfg 220 v xG' 5 .
ca P = V X I cyft{ I = P /V ;q" k|ofu] ug'x{ f;] \ .
o;/L lg:ss] f] current pSt 3/df Flow xG' 5 eGg] ae' mg\ x' f;] \ .
gk] fnL ahf/df pknAw x'g] Fuse dWo] dflysf] Calculation af6 lg:s]sf] current
eGbf dflyNnf] capacity sf] Fuse nfO{ pko'St kmo\ 'h dflgG5 .
10A sf] Fuse eGgfn] circuit df 10A current kj| fx eof] eg] kUng] Fuse
ae' mg\ 'k5{ .
-r_ k|fljlws zAbfjnL
Lead M Melting point sd ePsf] Ps wft'
Tin M ;]tf] /ªsf] Ps wft' (a soft silvery-white metal)
Current M On]S6f« ]g jf rfhs{ f] k|jfxsf sf/0f pTkGg x'g] zlSt
MCB M Switch h:t} sfd ug]{ cfw'lgs kmo\ 'h
;Gbe{ ;fdu|L

1. http://kcseelectricity.blogspot.com/2014/07/defects-of-simple-
electric-cell_11.html

2. http://www.thecircuitdetective.com/bkgrd.htm
3. http://www.electrical4u.com/miniature-circuit-breaker-or-mcb/
4. http://www.electrical4u.com/electrical-fuse-hrc-fuse-high-rupturing-

capacity/

96

PsfO M 11 kbfy{

cgd' flgt 3G6L M 12 -10 ;¢} flGts ± 2 ko| f]ufTds_

1. l;sfO pknlAw

x k/df0fs' f] agf6] sf] df]8n b]vfO{ On]S6«f]g, kf| ]6g / Go"6f« ]gsf u0' fx¿ atfpg

x of}lusx¿sf] c0f';q" n]Vg

x dG] 8l] nesf] k]l/of]l8s tflnsfsf] ;fdfGo kl/ro lbg

x h;+oH' otf kl/eflift ug{ / klxnf] 20 cf6] f tTTTjx¿sf] OnS] 6«fg] ljGof; x/] L
;+o'Hotf kTtf nufpg

x kf/dfl0fs ef/ / kf/dfl0fs ;ª\Vofsf] kl/efiff lbO{ o;sf cfwf/df k|f]6f]g,
Go6" «fg] / OnS] 6f« g] sf] ;ª\Vof kTtf nufpg

x cf0fljs ef/sf] kl/efiff lbg / cf0fljs ef/ lx;fa u/L lgsfNg

x /f;folgs k|ltlj|mof / ;dLs/0fsf] kl/efiff lbO{ s]xL ;fdfGo /f;folgs
kl| tljm| ofx¿nfO{ zAb / ;q" ;dLs/0fdf JoSt ug{

2. ljifoj:t' ljefhg / l;sfO ;fduL|

lbg ljifoj:t' l;sfO ;fdu|L

1 k/df0f', c0f' / k/df0fs' f] du' f, df]tLsf bfgf, k/df0fs' f] df]8n rf6{,
df8] n c0f'sf] df8] n, tf/

2 kf| 6] fg] , Go'6f« g] / On]S6«fg] sf k/df0f'sf] rf6{
u'0fx¿

3 Kff/df0fljs ;ªV\ of / ef/ kf/dfl0fs ef/ tyf On]S6' «f]g, kf| ]6f]g /
Go6' f« ]gsf] ;ª\Vof lgsfNg ko| fu] ul/g]
;"qsf] rf6{

4 klxnf] 20 tTTTjx¿sf] cfw'lgs k]l/ofl] 8s tflnsfcg';f/ aflx/L

OnS] 6«f]g ljGof; On]S6«f]g :ki6 xg' ] u/L agfOPsf] klxnf]
20 tTTTjsf] tflnsf

5 ;o+ 'Hotf cfwl' gs k]l/of]l8s tflnsfcg';f/ aflx/L
On]S6f« g] :ki6 xg' ] u/L agfOPsf] klxnf]
20 tTTTjsf] tflnsf

6 of}lusx¿sf] c0f';"q s]xL of}lusx¿sf] c0f';q" lgsfNg] tl/sf

97

k|bz{ g ul/Psf] rf6{

7 cf0fljs ef/ cf0fljs ef/ lgsfNg] tl/sf k|bz{g
ul/Psf] rf6{

8 k]l/ofl] 8s tflnsf, Df]G8l] nesf] k]l/of]l8s tflnsf / cfwl' gs

dG] 8l] nesf] kl] /of]l8s k]l/of]l8s tflnsf
tflnsf

9 /f;folgs k|ltlj|mof / DofUg]l;od l/ag, ;nfO, lvof nfu]sf]

;dLs/0f kmnfd

10 ;q" ;dLs/0f zAb / /f;folgs ;dLs/0fsf] rf6{

11/12 k|ofu] zfnf lj|mofsnfk rf6{ kk] /, kml] asn, wfuf,] s/] fpsf] u]8f
cyjf sIff cflb
ljm| ofsnfkcGtu{t ljleGg
tTTTjx¿sf] df]8n lgdf{0f /
k|:tt' Ls/0f

3. ljlzi6 p2]Zo, l;sfO ljm| ofsnfk / d"Nofªs\ g
lbg 1= k/df0f,' c0f' / k/df0f' df8] ]n
-s_ ljlzi6 p2]Zo

x k/df0f' / c0f'sf] kl/efiff lbg

x k/df0f' / c0fs' f] df]8n tof/ kfg{
-v_ l;sfO ;xhLs/0f ljm| ofsnfk
ljm| ofsnfk 1. c0f' / k/df0fs' f] cjwf/0ff

x sIffsf ljBfyL{x¿nfO{ ;ªV\ ofsf cfwf/df 5-6 ;d"xdf ljefhg ug{'xf];\ .
kT| o]s ;dx" df k/df0f' egs] f] s] xf] < c0f' egs] f] s] xf] < h:tf kZ| g ePsf]
Flash card ljt/0f ug'{xf];\ .

x oL k|Zg ;DaGwdf ;dx" ut ug{ nufpg'xf];\ . kT| o]s ;d"xsf] 5nkmndf
;xhLs/0f ugx{' f];\ . -;'?df ljBfyLn{ ] cl3Nnf] kf7 jf sIffdf k9s] f] s/' faf6
s]xL k|Zgx¿ ;fw] /] o;nfO{ rflxg] k"j1{ fg hfrF ug{ ;lsG5 _ . h:t}M

1= kbfy{ sn] fO{ elgG5 <
2= kbfy{ 6j' |mfpFb} uof] eg] s] xG' 5 < k/df0f' / c0f' egs] f s] xfn] fg\ <

98