copyright @ md shah jamal teachingbd · 1 †gvj m¨v‡mi zvcgvÎv 1k evov‡z ‡h cwigvb zv‡ci...
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1| Zvc MwZwe`¨v
(Thermodynamics)
‡gv: kvn& Rvgvj mnKvix Aa¨vcK (c`v_©weÁvb wefvM ) we G Gd kvnxb K‡jR XvKv ‡dvb: 01670 856105, 9125630, 9115369
ZvcgvÎv (Temperature): e¯‘i Zvcxq Ae¯’v‡K e¯‘i ZvcgvÎv e‡j| ZvcgvÎv ej‡Z e¯‘ KZUzKz Mig ev VvÛv Zv eySvq| ZvcgvÎv‡K ev T Øviv
cÖKvk Kiv nq| ZvcgvÎvi GKK ºC, K, ºF BZ¨vw`|
Zvc (Heat): Zvc GK cÖKvi kw³| hv cÖ‡qvM Ki‡j e¯‘ Mig nq Ges wbM©Z Ki‡j e¯‘ VvÛv nq Zv‡K Zvc e‡j| Zvc‡K
Q ev H Øviv Kiv nq| Zv‡ci GKK Ryj ev K¨vjwi| 1 K¨vjwi = 4.2 Ryj|
Zvc MwZwe`¨vi 1g m~Î (First Law of Thermodynamics): Ry‡ji g‡Z ÒhLbB †Kvb Kv‡Ri d‡j Zvc Drcbœ nq ev Zv‡ci d‡j KvR mvwaZ nq ZLb KvR I Zvc ci¯ú‡ii
mgvbycvwZKÓ|
e¨vL¨v: g‡b Kwi, W cwigvb Kv‡Ri d‡j Q cwigvb Zvc Drcbœ nj| G‡ÿ‡Î m~Î g‡Z,
W ∞ Q W = J Q GLv‡b J GKwU aªæe msL¨v| GB aªæe msL¨v‡K Zv‡ci hvwš¿K mgZv ev Ryj aªyeK e‡j|
weÁvbx K¬wmqv‡mi g‡Z hLbB †Kvb e¯‘ ev ms¯’vq Zvc mieivn Kiv nq ZLbB GB Zv‡ci wKQy Ask e¯‘ ev
ms¯’vi AšÍ©wbwnZ kw³ e„wׇZ e¨vq nq evKx Ask evwn¨K KvR m¤úv`‡b LiP nq| MwY‡Zi fvlvq
dQ = dU + dW GLv‡b dQ = †gvU cÖ Ë Zvc dU = AšÍ©wbwnZ kw³i cwieZ©b I dW = evwn¨K
m¤úvw`Z KvR| weÁvbx †nj¥R Gi g‡Z Ò kw³ Awebk¦i Ó | kw³ m„wó ev webvk Kiv hvq bv| †Kej GK kw³ Ab¨ GK ev
GKvwaK kw³‡Z iƒcvšÍwiZ Kiv hvq| hLbB GK kw³ A „k¨ n‡e ZLbB Aci kw³i Avwef©ve NU‡e| ZvB GB we‡k¦i †gvU
kw³i cwigvb AcwieZ©bxq|
Dc‡iv³ msMv n‡Z †h, kw³i e¨q Qvov KvR Kiv m¤¢e bq| Ggb †Kvb hš¿ Avwe®‹vi Kiv m¤¢e bq hv kw³ Qvov
Pj‡Z cv‡i|
Zv‡ci hvwš¿K mgZv (Mechanical equivalent of heat) : Ry‡ji Zvc MwZwe`¨vi 1g m~Î n‡Z Avgiv †h mgxKiY cvB Zv
nj W = JQ D³ mgxKi‡Y Q = 1 K¨vjwi n‡j W = J nq | A_©vr 1 K¨vjwi Zvc m¤úyb©iƒ‡c Kv‡R iƒcvšÍwiZ n‡j hZUzKz
KvR nq Zv‡K Zv‡ci hvwš¿K mgZv e‡j| hvwš¿K mgZv‡K J Øviv cÖKvk Kiv nq| J Gi gvb 4.2 Ryj/ K¨vjwi| J = 4.2
Ryj/ K¨jwi ej‡Z GB eywS †h, 1 K¨vjwi Zvc Kv‡R iƒcvšÍwiZ n‡j 4.2 Ryj KvR m¤úvw`Z nq|
ZvcMZxq cÖwµqv (Thermodynamic Process ): Pvc P, ZvcgvÎv T I AvqZb V ivwk¸‡jv‡K Zvc MZxq ¯’vbvsK ev Zvc
MZxq Pj ivwk e‡j| Zvc MZxq ’vbvs‡Ki mvnv‡h¨ †KvY e¨e¯’vi Ae ’v cÖKvk Ki‡j, †m Ae¯’v‡K Zvc MZxq Ae¯’v e‡j|
†h cwieZ©‡bi Kvi‡Y Zvc MZxq ¯’vbvs‡Ki gvb cwiewZ©Z nq †m cwieZ©b‡K ZvcMZxq cÖwµqv e‡j|
ZvcMZxq ¯’vbvsK (Thermodynamic co-ordinates): ZvcMZxq Av‡jvPbvi Rb¨ †Kvb e¨e¯’vi Ae ’v Pvc P , AvqZb V
I cig ZvcgvÎv T Gi mvnv‡h¨ cÖKvk Kiv nq| GB ivwk ¸wj‡K ZvcMZxq ¯’vbvsK e‡j|
ZvcMZxq Ae¯’v (Thermodynamic State): ZvcMZxq Av‡jvPbvi Rb¨ †Kvb e¨e¯’vi Ae ’v Pvc P, AvqZb V I cig
ZvcgvÎv T Gi mvnv‡h¨ cÖKvk Kiv nq| GB ivwk ¸wj‡K ZvcMZxq ¯’vbvsK ev Zvc MZxq Pj ivwk e‡j| ZvcMZxq
¯’vbvs‡Ki mvnv‡h¨ †KvY e¨e¯’vi Ae ’v cÖKvk Ki‡j †m Ae¯’v‡K ZvcMZxq Ae¯’v e‡j|
ZvcMZxq mvg¨ve¯’v (Thermodynamic Equilibrium): ‡Kvb wew”Qbœ e¨e¯’vi P‚ovšÍ AwePj Ae¯’v‡K ZvcMZxq mvg¨ve¯’v
e‡j| mvg¨ve¯’vq e¨e ’vi mKj we› y‡Z ZvcMZxq ¯’vbv¼ A_©vr Pvc P, AvqZb V I cig ZvcgvÎv T Gi gvb mgvb|
ZvcMZxq wm‡÷g ev e¨e¯’v (Thermodynamic system): ZvcMZxq wm‡÷g ej‡Z Zj ev †eóbx Øviv mxgve× †Kvb wbw ©ó
cwigvb e¯‘‡K eySvq| †hgb GKwU wc÷b hy³ wmwjÛv‡i A_ev GKwU †ejy‡b Ave× M¨vm|
AšÍ ’ kw³ (Internal Energy): †Kvb e¨e¯’vi Af¨šÍixb kw³B AšÍ ’ kw³| e¨e¯‘vi GB kw³ Ab¨vb¨ kw³‡Z iæcvšÍwiZ
n‡Z cv‡i| GB kw³ c`v‡_©i Af¨šÍixb MV‡bi Dci wbf©i K‡i| AšÍ ’ kw³ AYy¸‡jvi wefe kw³ I MwZkw³i ‡hvMdj|
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01| Zvc MwZwe`¨v (Thermodynamics) 2 Zvc cÖ‡qvM ev Zvc Acmvib Øviv AšÍ ’ kw³i cwieZ©b NUv‡bv hvq| Avevi e ‘i Dci KvR K‡i ev e¯‘i Øviv
KvR m¤úvw`Z n‡j AšÍ ’ kw³i cwieZ©b nq| AšÍ ’ kw³i cwieZ©b ïaygvÎ e¨e¯’vi cÖv_wgK I PzovšÍ Ae¯’vi Dci wbf©i
K‡i| M¨vm‡K msbwgZ Ki‡j AšÍ ’ kw³i e„w× cvq Avevi M¨vm‡K cªmvwiZ Ki‡j AšÍ ’ kw³ n«vm cvq|
iæ× Zvc cÖwµqvq M¨vm‡K msbwgZ Ki‡j Gi ZvcgvÎv e„w× cvq - Gi KviY:
iæ× Zvc cwieZ©‡b M¨v‡mi ZvcgvÎv KLbB w¯’i _v‡K bv| A_v©r iæ×Zvc cÖwµqvq M¨vm †Kvb Zvc MÖnb ev eR©b K‡i bv|
wKš‘ M¨vm Zvc MÖnb eR©b bv Ki‡jI M¨v‡mi AšÍt¯’ kw³ w¯’i _v‡K bv| hLb M¨vm‡K msbwgZ Kiv nq ZLb M¨v‡mi KvR
m¤úv`b Kiv nq| G‡Z M¨v‡mi kw³ e„w× cvq A_©vr M¨v‡mi AšÍt¯’ kw³i e„w× N‡U| KviY G †ÿ‡Î M¨vm Zvc eR©b Ki‡Z
cv‡i bv| G Rb¨ Gi ZvcgvÎv e„w× cvq|
M¨v‡mi Av‡cwÿK Zvc I †gvjvi ZvcaviY ÿgZvi (†gvjvi Av‡cwÿK Zvc) g‡a¨ m¤úK© (Relation between specific heat of gas and molar thermal capacity of gas): 1 †gvj M¨v‡mi ZvcgvÎv 1K evov‡Z ‡h cwigvb Zv‡ci cÖ‡qvRb Zv‡K †gvjvi Zvc aviY ÿgZv ev †gvjvi Av‡cwÿK Zvc
e‡j| †Kvb M¨v‡mi n msL¨K †gv‡ji ZvcgvÎv T cwigvb evov‡Z hw` Q Zv‡ci cÖ‡qvRb nq Z‡e
1 †gvj M¨v‡mi ZvcgvÎv 1K evov‡Z Zvc jvM‡e
TnQ
‡gvjvi Zvc aviY ÿgZv Tn
QC
1 ‡KwR M¨v‡mi ZvcgvÎv 1K evov‡Z ‡h cwigvb Zv‡ci cÖ‡qvRb Zv‡K M¨v‡mi Av‡cwÿK Zvc e‡j| †Kvb M¨v‡mi m ‡KwR
M¨v‡mi ZvcgvÎv T cwigvb evov‡Z hw` Q Zv‡ci cÖ‡qvRb nq Z‡e
1 kg M¨v‡mi ZvcgvÎv 1K evov‡Z Zvc jvM‡e
TmQ
M¨v‡mi Av‡cwÿK Zvc Tm
Q
ΔTMmΔQC
Mmn
fi AvbweK
fi ie¯‘
msL¨v gvj† bGLv‡
ev,
TmΔΔQMC
ev, Zvc Kcw¶Av‡ miM¨v‡ MC
A_©vr †gvjvi Zvc aviY ÿgZv = AvbweK fi × M¨v‡mi Av‡cwÿK Zvc
M¨v‡mi Av‡cwÿK Zvc: 1 ‡KwR M¨v‡mi ZvcgvÎv 1K evov‡Z ‡h cwigvb Zv‡ci cÖ‡qvRb Zv‡K M¨v‡mi Av‡cwÿK Zvc
e‡j|
w¯’i Pv‡c M¨v‡mi Av‡cwÿK Zvc (Specific heat of Gas at constant Pressure): Pvc w¯’i †i‡L 1 ‡KwR f‡ii M¨v‡mi ZvcgvÎv 1K e„w× Ki‡Z hZUzKz Zvc cÖ‡qvM Ki‡Z nq Zv‡K w¯’i Pv‡c M¨v‡mi
Av‡cwÿK Zvc e‡j|
w¯’i AvqZ‡b M¨v‡mi Av‡cwÿc Zvc (Specific heat of Gas at constant Volume): AvqZb w¯’i †i‡L 1 ‡KwR f‡ii M¨v‡mi ZvcgvÎv 1K e„w× Ki‡Z ‡h cwigvb Zv‡ci cÖ‡qvRb nq Zv‡K w¯’i AvqZ‡bi
M¨v‡mi Av‡cwÿK Zvc e‡j|
w¯’i Pv‡c M¨v‡mi †gvjvi Av‡cwÿK Zvc ev †gvjvi Zvc aviY ÿgZv (Molar specific heat of Gas at constant Pressure): Pvc w¯’i †i‡L 1 †gvj M¨v‡mi ZvcgvÎv 1K e„w× Ki‡Z hZUzKz Zvc cÖ‡qvM Ki‡Z nq Zv‡K w¯’i Pv‡c M¨v‡mi †gvjvi
Av‡cwÿK Zvc ev †gvjvi Zvc aviY ÿgZv e‡j| G‡K Cp
Øviv cÖKvk Kiv nq|
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01| Zvc MwZwe`¨v (Thermodynamics) 3
w¯’i AvqZ‡b M¨v‡mi †gvjvi Av‡cwÿc Zvc ev †gvjvi Zvc aviY ÿgZv (Molar specific heat of Gas at constant Volume): AvqZb w¯’i †i‡L 1 ‡gvj M¨v‡mi ZvcgvÎv 1K e„w× Ki‡Z ‡h cwigvb Zv‡ci cÖ‡qvRb nq Zv‡K w¯’i AvqZ‡bi M¨v‡mi
‡gvjvi Av‡cwÿK Zvc ev †gvjvi Zvc aviY ÿgZv e‡j| G‡K Cv Øviv cÖKvk Kiv nq|
GKwU Av`k© M¨v‡mi Rb¨ Cp
I Cv Gi g‡a¨ m¤úK© (Relation between Cp
and Cv ) ev , Cp
Cv = R Gi cÖgvY:
g‡b Kwi wc÷b hy³ GKwU wmwjÛv‡ii g‡a¨ P Pv‡c, T ZvcgvÎvq, V AvqZ‡b 1 †gvj Av`k© M¨vm Av‡Q| (wPÎ wb‡¤§)
Gevi M¨v‡m wKQy Zvc cÖ vb Kiv nj| G Zvc M¨v‡mi ZvcgvÎv I Pvc e„w× Ki‡e Ges AvqZb I e„w× †c‡Z PvB‡e| d‡j
wc÷bwU Dc‡ii w`‡K DV‡Z †Póv Ki‡e| wc÷b‡K c~‡e©i Ae¯’v‡b ivL‡Z n‡j A_©vr AvqZb w ’i ivLvi Rb¨ wc÷‡bi
Dci wKQy IRb Pvcv‡Z n‡e| g‡b Kwi dQ Zvc cÖ‡qvM Kiv nj Ges wc÷‡b dP IRb Pvwc‡q M¨v‡mi AvqZb V
AcwiewZ©Z ivLv nj|
dQ Zvc MÖnb K‡i M¨v‡mi ZvcgvÎv hw` dT cwigvb e„w× cvq|
Zvn‡j, dQ = 1. Cv dT [M„nxZ Zvc = fi × Avt Zvc × DòZv e„w× ]
ev, dQ = Cv dT... ... ... ... ... (1) Avevi Zvc MwZwe`¨vi 1g m~Î
dQ dUdW Cv dT =dU dWewn ’t Kv‡Ri cwigvb I (1) bs mgxKiY n‡Z dQ Gi gvbewm‡q] dU =Cv dT ... ... ... ... ... Gevi wc÷‡bi Dci †_‡K cÖv_wgK IRb †i‡L AwZwi³ dP IRb Zz‡j wb‡j wc÷b Dc‡ii w`‡K DV‡Z _vK‡e A_©vr
AvqZb e„w× cv‡e| [wPÎ - M]| AvqZb e„w×i Rb¨ M¨v‡mi wKQy KvR Ki‡Z n‡”Q| M¨v‡mi AšÍt¯’ kw³ e¨v‡q G KvR Ki‡Z
nq e‡j AšÍt¯’ kw³ n«vm cvq d‡j ZvcgvÎv I n«vm cvq| w¯’i Pv‡c M¨v‡mi ZvcgvÎv dT e„w×i Rb¨ M¨vm †h cwigvb KvR
Ki‡Q Zvi mgZzj¨ Zvc cÖ‡qvM Ki‡Z n‡e| A_©vr G‡ÿ‡Î †h AwZwi³ Zvc mieivn Ki‡Z n‡e Zvi cwigvb PdV| GLv‡b
M¨v‡mi AvqZb e„w×i cwigvb dV Ges cÖ`Ë w¯’i Pvc P| G‡ÿ‡Î mieivnK…Z Zvc dQ
dQ = 1. Cp dT
dQ = Cp dT... ... ... ... ... (3) Avevi Zvc MwZwe`¨vi 1g m~ÎwU nj
dQ = dU + dW dQ = dU + PdV [dW = PdV ] Cpd Cv dT + PdV [3 bs n‡Z dQ Ges 2 bs n‡ZdU Gi gvb ewm‡q|]
ev, Cpd Cv dT = PdV ev, Cp Cv d = PdV ... ... ... ... ... ... (4)
Avevi, †gvjvi M¨vm aªæeK R n‡j, 1 †gvj M¨v‡mi Rb¨ Avgiv Rvwb,
PV = RT ... ... ... ... ... ... ... (5) (5) bs mgxKiY‡K T Gi mv‡c‡ÿ e¨eKjb K‡i cvB,
RTdTdPV
dTd
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01| Zvc MwZwe`¨v (Thermodynamics) 4
ev,
dTdTR
dTdVP [P I R aªæe]
ev, RdTdVP
PdV = RdT ... ... ... ... ... ... ... (6) (4) bs mgxKi‡Y (6) bs mgxKi‡Yi gvb ewm‡q cvB,
Cp Cv d = RdT Cp Cv = R ... ... ... ... ... ... ... (7) BnvB CpI Cv g‡a¨ m¤úK©|
CpI Cv I AYycvZ‡K Øviv cÖKvk Kiv nq| A_©vr
V
P
CC
†h‡nZz Cp Cv = R Avevi R abvZ¡K msL¨v
CpCv , Avevi CpCv e‡j Gi gvb me mgq 1 Gi †ekx|
iæ× Zvcxq cwieZ©‡b M¨v‡mi Pvc I AvqZ‡bi g‡a¨ m¤úK© (Relation between Pressure and volume in an adiabatic Process) A_©vr PV
= aªæeK Gi cÖgvb I ZvcgvÎv I AvqZ‡bi g‡a¨ m¤úK© æeKaª1γTV | g‡b Kwi, 1 †gvj M¨vm‡K dQ cwigvb Zvc †`Iqvi d‡j Gi AvqZb I DòZvi cwieZ©b h_vµ‡g dV I dT nq| Zvc
MwZwe`¨vi 1g m~Î †_‡K cvB,
dQ = dU +dW dQ = dU + PdV ... ... ... ... ... ... (1) [dW = PdV ]
wKš‘ Avgiv Rvwb, 1 †gvj M¨v‡mi AšÍt¯’ kw³i e„w× dU nj w¯’i AvqZ‡b †gvjvi Av‡cwÿK Zvc Cv Ges ZvcgvÎv e„w× dT
Gi ¸Y d‡ji mgvb, A_©vr dU = Cv dT ... ... ... ... ... ... ... (2) (1) bs mgxKi‡Y dU = Cv dT ewm‡q cvB, dQ = Cv dT + PdV ... ... ... ... ... ... (3) wKš‘ iæ× Zvcxq cÖwµqvq dQ = 0, (3) bs mgxKi‡Y dQ = 0 ewm‡q cvB,
Cv dT + PdV = 0 ... ... ... ... ... ... ... ... (4) 1 ‡gvj Av`k© M¨v‡mi Rb¨ Avgiv Rvwb,
PV = RT ... ... ... ... ... ... ... (5) GB mgxKiY‡K AšÍiKjb K‡i cvB,
PdV +VdP = RdT
R
VdPPdV dT ev, Gi GB gvb (4) bs mgxKi‡Y ewm‡q cvB,
0PdVR
VdPPdV Cv
ev, CvPdV + CvVdP + RPdV = 0 ev, CvPdV + CvVdP + (Cp Cv)PdV = 0 ev, CvPdV + CvVdP + CpPdV CvPdV = 0 ev, CvVdP + CpPdV = 0
0 PdV CC
VdP v
p ev,
[Dfq cÿ‡K Cv Øviv fvM K‡i|]
ev, VdP + PdV = 0 V
PCC
V
dV γ P
dP , 0ev [ Dfq cÿ‡K PV Øviv fvM K‡i| ]
Gevi Dfq cÿ‡K mgvKjb K‡i cvB,
LogeP + LogeV = aªæeK ev, LogeP +LogeV= LogeK
ev, LogePV = LogeK
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01| Zvc MwZwe`¨v (Thermodynamics) 5ev, KPV
|)(cÖgvwYZ æeKaª PV ... ... ... ... ... ... (6) Avgiv Rvwb, PV = RT
VRTP ... ... ... ... ... ... (7)
Avevi Avgiv Rvwb, PVaªæeK ... ... ... ... ... (6)
æeKaª V
VRT [(7) bs n‡Z gvb ewm‡q|]
æeKaª 1RTV
æeKaª 1γTV (cÖgvwYZ) [R me©Rbxb M¨vm aªæeK]
BnvB M¨v‡mi iæ× Zvc cwieZ©‡b AvqZb I ZvcgvÎvi g‡a¨ m¤úK©|
Cp I Cv Gi gvb wbY©q (Calculation of Cp and Cv): T cwigvb DòZv e„w×i Rb¨ GKwU Av`k© M¨v‡mi AšÍt¯’ kw³i e„w× U n‡j, U = Cv T GLv‡b Cv w¯’i
AvqZ‡b M¨v‡mi †gvjvi Av‡cwÿK Zvc| GKwU GK civgvYyK M¨v‡mi AšÍt¯’ kw³ ïaygvÎ Gi AcmviY MwZ kw³i Kvi‡Y
nq| M¨v‡mi MwZZË¡ n‡Z Avgiv Rvwb,
AšÍt¯’ kw³
RTU23
dT DòZv e„w×i Rb¨ AšÍt¯’ kw³ dU cwigvb e„w× Ki‡j,
RdT23d U
dT CdUdT R 23 dT C vv
R 23 Cv
11v K mol J 8.31
23 C [R = 8.31 J mol-1 K-1]
11v K mol J 12.5 C
Avevi, Cp Cv = R Cp = R +Cv Cp = (8.31 +12.5) J mol-1 K-1 Cp =20.81 J mol-1 K-1
Gi ¸iæZ¡ (Zvrch©): CpI Cv I AYycvZ‡K Øviv cÖKvk Kiv nq| A_©vr
V
P
CC
, †ÿÎ we‡k‡l ¸iæZ¡c~Y© f~wgKv cvjb K‡i| M¨v‡m k‡ãi
†eM wbY©‡q Gi ¸iæZ¡ i‡q‡Q| iæ× Zvc cwieZ©‡b -Gi cÖ‡qvRbxZv Av‡Q| Zv Qvov M¨v‡mi †hvR¨Zv m¤úwK©Z Z_¨ †_‡K cvIqv hvq| GK cvigvYyweK M¨v‡mi Rb¨ =1.33 Ges wØcvigvYyweK M¨v‡mi Rb¨ =1.41I wZb cvigvYyweK
M¨v‡mi Rb¨ =1.66| -Gi M¨v‡mi cigvbyi msL¨vi Dci wbf©ikxj e‡j †Kvb M¨v‡mi AYy‡Z KqwU cigvYy Av‡Q Zv -Gi gvb wbY©q K‡i Rvbv hvq| †h‡nZz Cp Cv = R Avevi R abvZ¡K msL¨v CpCv , Avevi CpCv e‡j Gi gvb
me mgq 1 Gi †ekx|
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01| Zvc MwZwe`¨v (Thermodynamics) 6iƒ×Zvc †jL m‡gvò †jL A‡cÿv Lvov (An adiabatic Carve is Steeper than Isothermal Curve) : iæ×Zvc cwieZ©‡bi †ÿ‡Î, Avgiv Rvwb,
PV = aªæeK, GB mgxKiY †K e¨eKjb K‡i cvB,
0dPVdVVP 1
V
dVVPdP1
VVP
dVdP
Q
1
(1) VP
dVdP
Q
... ... ...
cybivq, m‡gvò cwieZ©‡b, PV = aªæeK, GB mgxKiY †K e¨eKjb K‡i cvB,
PdV + VdP = 0
(2) ... ... ... VP
dVdP
T
mgxKiY (1) ‡K (2) Øviv fAM K‡i cvB,
VPVP
dVdPdVdP
T
Q
TdVdPdVdP
Q
AZGe,
Xvj iLvi† gvòm‡
Xvj iLvi† Zvcxq ev, iæ× Zvcxq‡iLvi Xvj = m‡gvò †iLvi Xvj ×
wKš‘ Gi gvb 1 A‡cÿv †ekx| myZivs, mgxKiY (3) †_‡K ejv hvq †h, iæ×Zvc †j‡Li Xvj ev bwZ (Slope) m‡gvò
†j‡Li Xvj ev bwZi | †h †jL wP‡Îi Xvj hZ †ekx †m †jLwPÎ ZZ †ekx Lvov| myZivs iƒ×Zvc †jL m‡gvò †jL A‡cÿv
Lvov|
m‡gvò cÖwµqv (Isothermal Process): Pvc cwieZ©b Kivi d‡j hLb †Kvb M¨v‡mi AvqZ‡bi cwieZ©b nq, wKš‘ ZvcgvÎvi †Kvb cwieZ©b nq bv, †m cwieZ©b‡K
m‡gvò cwieZ©b e‡j| †h cÖwµqvq G cwieZ©b msNwUZ nq Zv‡K m‡gvò cÖwµqv e‡j|
iæ×Zvcxq cÖwµqv (Adiabatic Process): ‡h cwieZ©‡b M¨v‡mi Pvc I AvqZ‡bi cwieZ©b nq wKš‘ cÖwµqvaxb M¨vm Zvc MÖnY ev eR©b Ki‡Z cv‡i bv, †m cwieZ©b‡K
iæ× Zvcxq cwieZ©b e‡j Ges †h cÖwµqvq G cwieZ©b msNwUZ nq Zv‡K iæ×Zvcxq cÖwµqv e‡j|
m‡gvò I iæ×Zvc cÖwµqvi g‡a¨ cv_©K¨t
µwgK m‡gvò cÖwµqv iæ×Zvc cÖwµqv
1|
w¯’i ZvcgvÎvq †h cÖwµqv m¤úvw`Z nq Zv‡K
m‡gvò cÖwµqv e‡j|
‡h cÖwµqv m¤úv`b Kv‡j cwi‡e‡ki mv‡_ Zv‡ci
Av`vb cÖ vb nqbv Zv‡K iæ×Zvc cÖwµqv e‡j|
2| m‡gvò cÖwµqvq ZvcgvÎv w¯’i _v‡K| iæ×Zvc cÖwµqvq ZvcgvÎv cwiewZ©Z nq|
3| GUv axi cÖwµqv GUv ªæZ cÖwµqv|
4| m‡gvò cÖwµqvq PV = aªæeK nq|
iæ×Zvc cÖwµqvq PV = aªæeK nq|
5| m‡gvò †jL Kg Lvov| iæ×Zvc †jL AwaK Lvov|
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01| Zvc MwZwe`¨v (Thermodynamics) 7m‡gvò cÖwµqvq †Kvb wm‡÷g KZ…K K…Z KvR wm‡÷‡g mieivnK…Z Zvc kw³i mgvbt
aiv hvK, Avgv‡`i wm‡÷g n‡”Q GKwU M¨vmfwZ© wmwjÛvi hvi mv‡_ GKwU bobÿg wc÷b
jvMv‡bv Av‡Q| wmwjÛvi †`Iqv‡ji ga¨ w`‡q kw³ wm‡÷‡g cÖ‡ek Ki‡Z wK¤v wm‡÷g
†_‡K †ewi‡q †h‡Z cv‡i|
hw` wm‡÷‡g Lye ax‡i ax‡i kw³ mieivn Kiv hvq Zvn‡j M¨v‡m Pvc I AvqZ‡bi cwieZ©b
n‡e hw`I Gi ZvcgvÎvi †Kvb cwieZ©b n‡e bv| Giƒc cwieZ©b‡K m‡gvò cwieZ©b e‡j|
Gi d‡j M¨v‡mi †h cÖmviY nq m‡gvò cÖmviY e‡j|
m‡gvò cÖwµqvq pV ˆiwLK wP‡Î †`Lvb n‡q‡Q| GB ˆiwLK wP·K m‡gv‡iL e‡j|
m‡gvò cÖwµqvq DòZv w¯’i _v‡K e‡j wm‡÷‡gi AšÍt¯’ kw³i †Kvb cwieZ©b nq bv| A_©vr dU = 0 |
myZivs, Zvc MwZwe`¨vi cÖ_g m~Î †_‡K cvB, dQ = 0 + dW dWdQ A_©vr m‡gvò cÖwµqvq †Kvb wm‡÷g KZ…K K…Z
KvR wm‡÷‡g mieivnK…Z Zvc kw³i mgvb| m‡gvò cÖwµqvq 2211 VpVp n‡e|
cÖZ¨vMvgx cÖwµqv (Reversible Process):
‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b K‡i Ges m¤§yLeZ©x I wecixZgyLx cÖwµqvi cÖwZ ¯Í‡i Zvc I Kv‡Ri djvdj mgvb I
wecixZ †mB cÖwµqv‡K cÖZ¨vMvgx cÖwµqv e‡j| eid Zvc †kvlY K‡i cvwb‡Z cwiYZ nq| Avevi †mB cvwb †_‡K Zvc
mgcwigvb Zvc AcmviY Ki‡j Zv cybivq ei‡d cwiYZ nq| GwU cÖZ¨vMvgx cÖwµqvi GKwU D`vniY|
AcÖZ¨vMvgx cÖwµqv (Irreversible Process): ‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b Ki‡Z cv‡i bv A_©vr m¤§yLeZ©x I wecixZgyLx cÖwZ ¯Í‡i Zvc I Kv‡Ri djvdj mgvb
I wecixZ nq bv †mB cÖwµqv‡K AcÖZ¨vMvgx cÖwµqv e‡j| ywU e¯‘i g‡a¨ Nl©‡Yi d‡j †h Zvc m„wó nq Zv GKwU
AcÖZ¨vMvgx cÖwµqv KviY Nl©‡bi weiæ‡× †h KvR nq ZvB Zv‡c cwiYZ nq Ges H Zvc‡K †Kvbfv‡eB Kv‡R iƒcvšÍwiZ
Kiv hvq bv|
cÖZ¨vMvgx cÖwµqv I AcÖZ¨vMvgx cÖwµqvi g‡a¨ cv_©K¨ (Distinction between reversible and irreversible process): cÖZ¨vMvgx cÖwµqv AcÖZ¨vMvgx cÖwµqv
1| ‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b K‡i Ges
m¤§yLeZ©x I wecixZgyLx cÖwµqvi cÖwZ ¯Í‡i Zvc I Kv‡Ri
djvdj mgvb I wecixZ †mB cÖwµqv‡K cÖZ¨vMvgx cÖwµqv
e‡j|
1| ‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b Ki‡Z cv‡i bv
A_©vr m¤§yLeZ©x I wecixZgyLx cÖwZ ¯Í‡i Zvc I Kv‡Ri
djvdj mgvb I wecixZ nq bv †mB cÖwµqv‡K
AcÖZ¨vMvgx cÖwµqv e‡j|
2| Kvh©wbe©vnK e ‘ cÖv_wgK Ae¯’vq wd‡i Av‡m| 2| Kvh©wbe©vnK e¯‘ cÖv_wgK Ae¯’vq wd‡i Avm‡Z cv‡i
bv|
3| GwU GKwU axi cÖwµqv| 3| GwU GKwU ªæZ cÖwµqv|
4| GB cÖwµqvq wm‡÷‡gi ZvcMZxq mvg¨ve¯’v eRvq
_v‡K|
4| GB cÖwµqvq wm‡÷‡gi ZvcMZxq mvg¨ve¯’v eRvq
_v‡K& bv |
BwÄb (Engine): ‡h h‡š¿ Zvc kw³ hvwš¿K kw³‡Z iƒcvšÍwiZ nq Zv‡K Zvc BwÄb e‡j| BwÄb cÖavYZ yB cÖKvi h_vt- 1| AšÍ©`nb BwÄb I
2| ewn ©nb BwÄb|
ZvcMwZwe`¨vi wØZxq m~Î (Second Law of Thermodynamics): K‡b©vi wee„wZ: †Kvb wbw ©ó cwigvb Zvc kw³‡K m¤úyY©iƒ‡c hvwš¿K kw³‡Z iƒcvšÍ‡i mÿg Ggb hš¿ wbg©vb m¤¢e bq|
K¬wmqv‡mi wee„wZ: evB‡ii kw³i mvnvh¨ Qvov †Kvb ¯qswµq h‡š¿i c‡ÿ wb¤œ DòZvi e¯‘ n‡Z D”PZi DòZvi e¯‘‡Z
Zv‡ci ¯’vbvšÍi m¤¢e bq|
cøv‡¼i wee„wZ: Ggb †Kvb BwÄb ˆZix m¤¢e bq, †hUv †Kvb e¯‘ †_‡K Zvc MÖnY K‡i Aweivgfv‡e Kv‡R cwiYZ Ki‡e A_P
cwi‡e‡ki †Kvb cwieZ©b n‡e bv|
‡Kjwf‡bi wee„wZ: ‡Kvb e¯‘‡K Gi cwicv‡k¦©i kxZjZg Ask n‡Z AwaKZi kxZj K‡i kw³i Aweivg mieivn cvIqv
m¤¢e bq|
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01| Zvc MwZwe`¨v (Thermodynamics) 8Bwćbi Zvcxq `ÿZv (Efficiency of a Engine): ‡Kvb Zvc BwÄb Øviv Kv‡R iƒcvšÍwiZ Zvc kw³i cwigvb Ges BwÄb
Øviv †kvwlZ Zvc kw³i AbycvZ‡K Bwćbi Zvcxq `ÿZv e‡j| G‡K Øviv cÖKvk Kiv nq| msÁv g‡Z,
Zvcxq `ÿZv,
kw³ Zvc kvwlZ† Øviv BwÄb
kw³ Zvc Øviv BwÄb iƒcvšÍwiZ
e¨vL¨v t †Kvb BwÄb hw` T1 ZvcgvÎvq Zvc Drm ‡_‡K Q1 Zvc ‡kvlY K‡i Ges T2 ZvcgvÎvq Q2 Zvc eR©b K‡i, Zvn‡j
BwÄb Øviv Kv‡R iƒcvšÍwiZ Zvc kw³i cwigvb = (Q1-Q2)|
1
21
QQQ
| Bwćbi Zvcxq `ÿZv‡K kZKivq cÖKvk Ki‡j Zvcxq `ÿZvi ivwkgvjv n‡e,
% 1001
21
Q
QQ % 100 1
2
1
1
ev,
% 1001 1
2
Zvc ZvcgvÎvi mgvbycvwZK, A_©vr, 11 TQ Ges 22 TQ d‡j, % 10011
2
TT
K‡Y©vi BwÄb (Carnot's Engine): Zvckw³‡K hvwš¿K kw³‡Z iƒcvšÍwiZ Kivi Rb¨ mv`x K‡b©v mKj †`vlΤœwU gy³ †h
Av`k© h‡š¿i Kíbv K‡ib Zv‡K K‡b©v BwÄb e‡j|
K‡b©v BwÄb GKwU Av`k© Bwćbi aviYvgvÎ, ev¯Í‡e Gi iƒcvšÍi m¤¢e nqwb| K‡b©v Bwćbi PviwU Ask| Ask PviwU (1)
wmwjÛvi (2) ZvcDrm (3) Zvc MÖvnK (4) Zvc AšÍiK e¯‘ ; wb‡¤œ wPÎmn wewfbœ Ask eY©bv Kiv nj|
wmwjÛvi (Cylinder): GKwU wmwjÛvi C| wmwjÛviwUi †`Iqvj m¤ú~Y© Zvc AšÍiK c`v_© Ges Zj‡`k m¤ú~yY© Zvc cwievnK
c`v_© Øviv ˆZix| Gi wfZ‡i m¤ú~Y© Zvc AšÍiK c`v‡_© ˆZix GKwU wc÷b P Nl©Ynxbfv‡e PjvPj Ki‡Z cv‡i| wmwjÛv‡ii
wfZi Kvh©wbe©vnK e¯‘ wn‡m‡e Av`k© M¨vm †bqv nq|
ZvcDrm: D”P Zvc aviYÿgZv m¤úbœ GKwU DËß e¯‘ hv T1 ZvcgvÎvq Av‡Q Ges Zv‡ci Drm wn‡m‡e KvR K‡i| Gi
ZvcgvÎv me© v w¯’i _v‡K, Zv‡ci Av`vb cÖ v‡b ZvcgvÎv KL‡bv cwieZ©b nq bv|
Zvc MÖvnK: D”P Zvc aviYÿgZv m¤úbœ T2 ZvcgvÎvq GKwU kxZj e¯‘ hv Zvc MÖvnK wn‡m‡e KvR K‡i| Gi ZvcgvÎvI
me© v w¯’i _v‡K, Zv‡ci Av`vb cÖ v‡b ZvcgvÎv KL‡bv cwieZ©b nq bv|
Zvc AšÍiK e¯‘: m¤ú~Y© Zvc AšÍiK c`v‡_©i ˆZix GKwU Avmb hvi Dci wmwjÛviwU emvb _v‡K|
K‡b©vi Pµ (Carnot's Cycle): †h we‡kl cÖwµqvq KvR Ki‡j GKwU Av`k© Zvc BwÄb Z_v K‡b©v BwÄb Aweivg kw³
mieivn Ki‡Z cv‡i Zv‡K K‡b©v Pµ e‡j| K‡b©v P‡µ cÖZ¨vMvgx cÖwµqvi gva¨‡g Kvh©wbe©vnK e¯‘ Drm †_‡K Zvc MÖnb K‡i
GKwU wbw ©ó Pvc, AvqZb I ZvcgvÎv n‡Z Avi¤¢ K‡i GKwU m‡gvò cÖmviY I GKwU iæ×Zvcxq cÖmviY Ges GKwU m‡gvò
m‡¼vPb I GKwU iæœ×Zvcxq m‡¼vP‡bi gva¨‡g Zv‡ci wKQy Ask Kv‡R iƒcvšÍi K‡i Ges evKx Ask Zvc MÖvn‡K eR©b K‡i
Avw` Ae¯’vq wd‡i Av‡m| Av`k© M¨vm‡K PviwU ch©v‡qi g‡a¨w`‡q AwZµg Kiv‡bv nq|
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01| Zvc MwZwe`¨v (Thermodynamics) 9cÖ_g ch©vq (First Operation): cÖ_‡g wmwjÛvi C †K Zvc Dr‡mi Dci emv‡bv
nq| Lye Aímg‡qi g‡a¨ wmwjÛv‡i Ave× M¨v‡mi ZvcgvÎv Dr‡mi ZvcgvÎvi mgvb
nq|aiv hvK, GB Ae¯’vq M¨v‡mi Pvc I AvqZb h_vµ‡g P1I V1 nq hv wb‡ ©kK
wP‡Îi A we› y Øviv wb‡ ©k Kiv n‡q‡Q| GLb Av`k© M¨vm‡K m‡gvò cÖwµqvq
cÖmvwiZ n‡Z w`‡j cÖwµqv †k‡l Gi Pvc I AvqZb h_vµ‡g P2I V2 nq hv
wb‡ ©kK wP‡Îi B we› y Øviv wb‡ ©k Kiv n‡q‡Q| AB †iLv Øviv M¨v‡mi m‡gvò
cÖmviY †`Lv‡bv n‡q‡Q Ges K…Z KvR, W1=ABGE †ÿ‡Îi †ÿÎd‡ji mgvb|
wØZxq ch©vq (Second Operation): Gevi wmwjÛvi C †K Zvc-AšÍiK Avm‡bi Dci emv‡bv nq Ges Ave× M¨vm‡K
iæ×Zvcxq fv‡e cÖmvwiZ n‡Z †`Iqv nq| cÖwµqv †k‡l M¨v‡mi Pvc I AvqZb h_vµ‡g P3I V3 nq hv wb‡ ©kK wP‡Îi C
we› y Øviv wb‡ ©k Kiv n‡q‡Q| iæ× Zvcxq cÖmvi‡Yi d‡j M¨v‡mi ZvcmvÎv n«vm †c‡q Zvc MÖvn‡Ki ZvcgvÎv T2 Gi mgvb
nq| wP‡Î BC †iLv Øviv M¨v‡mi iæ× Zvcxq cÖmviY †`Lv‡bv n‡q‡Q Ges GB cÖmvi‡Y K…Z KvR, W2=BCHG †ÿ‡Îi
†ÿÎd‡ji mgvb|
Z…Zxq ch©vq (Third Operation): Gevi wmwjÛvi C †K ZvcMÖvn‡Ki Dci ewm‡q Avevi M¨v‡mi Pvc e„w× Ki‡j wcób
Øviv M¨v‡mi Dci KvR m¤úvw`Z n‡e| d‡j M¨v‡mi AšÍt¯’ kw³ e„w× cv‡e| wKš‘ Ave× M¨vm e„w× cÖvß AšÍt¯’ kw³
Zvciƒ‡c ZvcMÖvn‡K eR©b K‡i ZvcgvÎv ZvcMÖvn‡Ki mgvb A_©vr T2 eRvq ivL‡e| GB Ae ’vq Ave× M¨v‡mi Pvc I
AvqZb h_vµ‡g P4 I V4 nq hv wb‡ ©kK wP‡Îi D we› y Øviv wb‡ ©k Kiv n‡q‡Q| wP‡Î CD †iLv m‡gvò ms‡KvPb wb‡ ©k
K‡i Ges GB m‡¼vP‡bi d‡j K…Z KvR, W3=CDFH †ÿ‡Îi †ÿÎd‡ji mgvb|
PZz_© ch©vq (Fourth Operation): ‡kl ch©v‡q wmwjÛvi C †K cybivq Zvc-AšÍiK Avm‡bi Dci emv‡bv nq Ges
iæ×Zvcxqfv‡e Ave× M¨v‡mi Dci Pvc evov‡bv nq| d‡j Gi AvqZb n«vm cvq| Ave× M¨v‡mi Dci KvR m¤úvw`Z
nIqvq Gi ZvcgvÎv e„wׇc‡q cybivq Dr‡mi ZvcgvÎv T1 Gi mgvb nq| GB Ae ’vh M¨v‡mi Pvc I AvqZb cybivq
h_vµ‡g P1 I V1 nq hv wb‡ ©kK wP‡Îi A we› y wb‡ ©k K‡i A_©vr Ave× M¨vm Avw` Ae¯’vq wd‡i Av‡m| wP‡Î DA †iLv
Ave× M¨v‡mi iæ× Zvcxq m‡¼vPb †`Lv‡bv n‡q‡Q d‡j K…Z KvR, W4=DAEF †ÿ‡Îi †ÿÎd‡ji mgvb|
GLv‡b W1 I W2 Ave× M¨vm Øviv K…Z KvR e‡j abvZ¥K n‡e Ges W3 I W4 Ave× M¨v‡mi Dci K…Z KvR e‡j FbvZ¥K
n‡e| d‡j Ave× e¯‘ Øviv †gvU K…Z KvR,
W= W1+ W2 - W3 - W4
W= ABGE + BCHG - CDFH - DAEF W= ABCD †ÿ‡Îi †ÿÎd‡ji mgvb| myZivs GKwU K‡b©v P‡µ Kvh©wbe©vnK e¯‘ Øviv m¤úvw`Z KvR wb‡ ©kK wP‡Î ywU
m‡gvò †iLv I ywU iæ×Zvcxq †iLv Øviv Ave× †ÿ‡Îi †ÿÎd‡ji mgvb|
GbUªwc (Entropy): ‡Kvb wm‡÷‡g kw³ _vK‡jB †h Zv‡K cÖ‡qvRbxq Kv‡R jvMv‡bv hv‡e Ggb †Kvb wbðqZv †bB| GUv
wbf©i K‡i wm‡÷‡gi ZvrÿwYK Ae¯’vi Dc‡i| Avgiv Rvwb †Kvb M¨vm‡K iæ×Zvcxq cÖwµqvq m¼zwPZ Ki‡j M¨v‡mi Dci
†h KvR Kiv nq Zvi d‡j M¨v‡mi Aš’t¯’kw³ I ZvcgvÎv †e‡o hvq| Avevi iæ×Zvcxq cÖwµqvq †Kvb M¨vm‡K cÖmvwiZ
n‡Z w`‡j M¨vm‡K wKQy KvR Ki‡Z nq| d‡j M¨v‡mi Aš’t¯’kw³ I ZvcgvÎv K‡g hvq| myZivs †`Lv hvq †h, iæ×Zvcxq
cÖwµqvq M¨v‡mi AšÍt¯’kw³ I ZvcgvÎv Df‡qiB cwieZ©b nq| wKš‘ m‡gvò cÖwµqvq †hgb ZvcgvÎv w¯’i _v‡K iæ×Zvcxq
cÖwµqvq †Zgwb †Kvb GKwU ivwk w¯’i _v‡K| K¬wmqvm GB ivwkwUi bvg †`b GbUªwc| iæ×Zvcxq cÖwµqvq e¯‘i †h Zvcxq
ag© w¯’i _v‡K Zv‡K GbUªwc e‡j| GbUªwc GKwU †fŠZ ivwk, G‡K S Øviv cÖKvk Kiv nq|
hw` †Kvb wm‡÷g T ZvcgvÎvq dQ cwigvb Zvc MÖnY ev eR©b Kivi d‡j GbUªwci cwieZ©b ds nq Z‡e
TdQds n‡e|
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01| Zvc MwZwe`¨v (Thermodynamics) 10‡Kvb wm‡÷‡gi kw³ iƒcvšÍ‡ii AÿgZv ev Am¤¢ve¨Zv‡K ev iƒcvšÍ‡ii Rb¨ kw³i AcÖvßZv‡K GbUªwc e‡j|
GbUªwci e¨vL¨v nj e ‘i iæ×Zvcxq cÖwµqvq GbUªwc w¯’i _v‡K:
†Kvb e¯‘i GbUªÖwci cig gvb AvRI Rvbv m¤¢e nqwb| Z‡e †Kvb e¯‘ hw` Zvc MÖnb ev eR©b K‡i, Zvn‡j e¯‘i GbUªwci
cwieZ©b nq| †Kvb wm‡÷‡gi ZvcgvÎv mv‡c‡ÿ M„nxZ ev ewR©Z Zvc cwieZ©‡bi nvi Øviv GbUªwci cwieZ©b cwigvc Kiv
nq|
hw` †Kvb wm‡÷g T ZvcgvÎvq dQ cwigvb Zvc MÖnY ev eR©b Kivi d‡j GbUªwci cwieZ©b ds nq Z‡e
TdQds n‡e|
Dc‡iv³ mgxKiY n‡Z †`Lv hvq †h, iæ×Zvcxq cÖwµqvq †h‡nZz Kvh©wbe©vnK e¯‘i mv‡_ evB‡ii Zv‡ci †Kvb Av`vb cÖ vb
nqbv Kv‡RB, dQ=0 | myZivs iæ×Zvcxq cÖwµqvq GbUªwci cwieZ©b, 00
TTdQdS A_©vr iæ×Zvcxq cÖwµqvq
GbUªwci cwieZ©b nq bv A_©vr iæ×Zvcxq cÖwµqvq GbUªwci w¯’i _v‡K| myZivs †Kvb e¯‘i GbUªwc ej‡Z Avgiv Ggb GKUv
‡fŠZ ivwk‡K eywS hv e¯‘i iæ×Zvcxq cÖZ¨vMvgx cÖwµqvq me© v w¯’i _v‡K| GbUªwci cwieZ©‡bi GKK JK-1 |
cÖZ¨veZ©x cÖwµqvq GbUªwc w¯’i _v‡K I AcÖZ¨veZ©x cÖwµqvq GbUªwc e„w× cvq t
cÖZ¨veZ©x cÖwµqvq GbUªwc w¯’i _v‡K:
K‡b©vi Pµ GKwU cÖZ¨veZ©x cÖwµqv| G‡Z ywU m‡gvò †iLv I ywU iæ×Zvcxq †iLv Øviv m„ó AB I CD ywU m‡gvò †iLv
Ges BC I DA ywU iæ× Zvcxq †iLv| ‡h‡nZz iæ×Zvcxq cÖwµqvq GbUªwc w¯’i _v‡K myZivs m‡gvò AB I CD Gi †ÿ‡Î
GbUªwci cwieZ©b NU‡e|
AB Gi †ÿ‡Î Zvc 1Q I ZvcgvÎv 1T n‡j GbUªwci cwieZ©b,
1
11 T
Qds
Ges CD Gi †ÿ‡Î Zvc 2Q I ZvcgvÎv 2T n‡j GbUªwci cwieZ©b,
2
22 T
Qds
†gvU GbUªwci cwieZ©b
2
2
1
121 T
QTQdsdsds
wKš‘ cÖZ¨vMvgx cÖwµqvq K‡b©vP‡µ,
2
2
1
1
TQ
TQ
G‡ÿ‡Î †gvU GbUªwci cwieZ©b, 02
2
1
121
TQ
TQdsdsds A_©vr cÖZ¨veZ©x cÖwµqvq GbUªwci cwieZ©b k~b¨|
myZivs cÖZ¨veZ©x cÖwµqvq GbUªwc w¯’i _v‡K|
AcÖZ¨veZ©x cÖwµqvq GbUªwc e„w× cvq:
aiv hvK, ywU e¯Íy A I B cwicv‡k¦©i cÖfve †_‡K gy³ Ae¯’vq ci¯ú‡ii ms¯ú‡k© Av‡Q| e¯‘Øq Ges G‡`i ms‡hvM¯’j Zvc
mycwievnx| e ‘؇qi ZvcgvÎv h_vµ‡g 1T I ;2T ;21 TT Zvc DËß e¯‘ †_‡K kxZj e¯‘‡Z mÂvwjZ n‡e| †m Zvc Avi DËß
e¯‘‡Z wd‡i Avm‡e bv| AZGe GwU GKwU AcÖZ¨veZ©x cÖwµqv|
awi, AwZ Aí mg‡q dQ cwigvb Zvc A †_‡K B †Z mÂvwjZ nq| A e¯‘ dQ cwigvb Zvc nvivq, B
e¯‘ dQ cwigvb Zvc AR©b K‡i| A e¯‘i GbUªwc n«vm ;1T
dQ B e¯‘i GbUªwc e„w× ;
2TdQ
mgMÖ e¨e¯’vq †gvU GbUªwci cwieZ©b,
12 TdQ
TdQds
G‡ÿ‡Î, †gvU GbUªwci cwieZ©b GKwU abvZ¥K ivwk; KviY, 21 TT |
AZGe, AcÖZ¨veZ©x cÖwµqvq GbUªwc e„w× cvq| A_ev Ab¨fv‡e ejv hvq,
¯ZtùzZ© cÖwµqv †mw`‡KB msNwUZ nq †h w`‡K GbUªwc e„w× cvq
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01| Zvc MwZwe`¨v (Thermodynamics) 11cÖZ¨vMvgx cÖwµqv (Reversible Process): ‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b K‡i Ges m¤§yLeZ©x I wecixZgyLx cÖwµqvi cÖwZ ¯Í‡i Zvc I Kv‡Ri djvdj mgvb I
wecixZ †mB cÖwµqv‡K cÖZ¨vMvgx cÖwµqv e‡j| eid Zvc †kvlY K‡i cvwb‡Z cwiYZ nq| Avevi †mB cvwb †_‡K Zvc
mgcwigvb Zvc AcmviY Ki‡j Zv cybivq ei‡d cwiYZ nq| GwU cÖZ¨vMvgx cÖwµqvi GKwU D`vniY|
AcÖZ¨vMvgx cÖwµqv (Irreversible Process): ‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b Ki‡Z cv‡i bv A_©vr m¤§yLeZ©x I wecixZgyLx cÖwZ ¯Í‡i Zvc I Kv‡Ri djvdj mgvb
I wecixZ nq bv †mB cÖwµqv‡K AcÖZ¨vMvgx cÖwµqv e‡j| ywU e¯‘i g‡a¨ Nl©‡Yi d‡j †h Zvc m„wó nq Zv GKwU
AcÖZ¨vMvgx cÖwµqv KviY Nl©‡bi weiæ‡× †h KvR nq ZvB Zv‡c cwiYZ nq Ges H Zvc‡K †Kvbfv‡eB Kv‡R iƒcvšÍwiZ
Kiv hvq bv|
cÖZ¨vMvgx cÖwµqv I AcÖZ¨vMvgx cÖwµqvi g‡a¨ cv_©K¨ (Distinction between reversible and irreversible process): cÖZ¨vMvgx cÖwµqv AcÖZ¨vMvgx cÖwµqv
1| ‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b K‡i Ges
m¤§yLeZ©x I wecixZgyLx cÖwµqvi cÖwZ ¯Í‡i Zvc I Kv‡Ri
djvdj mgvb I wecixZ †mB cÖwµqv‡K cÖZ¨vMvgx cÖwµqv
e‡j|
1| ‡h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b Ki‡Z cv‡i bv
A_©vr m¤§yLeZ©x I wecixZgyLx cÖwZ ¯Í‡i Zvc I Kv‡Ri
djvdj mgvb I wecixZ nq bv †mB cÖwµqv‡K
AcÖZ¨vMvgx cÖwµqv e‡j|
2| Kvh©wbe©vnK e ‘ cÖv_wgK Ae¯’vq wd‡i Av‡m| 2| Kvh©wbe©vnK e¯‘ cÖv_wgK Ae¯’vq wd‡i Avm‡Z cv‡i
bv|
3| GwU GKwU axi cÖwµqv| 3| GwU GKwU ªæZ cÖwµqv|
4| GB cÖwµqvq wm‡÷‡gi ZvcMZxq mvg¨ve¯’v eRvq
_v‡K|
4| GB cÖwµqvq wm‡÷‡gi ZvcMZxq mvg¨ve¯’v eRvq
_v‡K& bv |
BwÄb (Engine): ‡h h‡š¿ Zvc kw³ hvwš¿K kw³‡Z iƒcvšÍwiZ nq Zv‡K Zvc BwÄb e‡j| BwÄb cÖavYZ yB cÖKvi h_vt- 1| AšÍ©`nb BwÄb I
2| ewn ©nb BwÄb|
ZvcMwZwe`¨vi wØZxq m~Î (Second Law of Thermodynamics): K‡b©vi wee„wZ: †Kvb wbw ©ó cwigvb Zvc kw³‡K m¤úyY©iƒ‡c hvwš¿K kw³‡Z iƒcvšÍ‡i mÿg Ggb hš¿ wbg©vb m¤¢e bq|
K¬wmqv‡mi wee„wZ: evB‡ii kw³i mvnvh¨ Qvov †Kvb ¯qswµq h‡š¿i c‡ÿ wb¤œ DòZvi e¯‘ n‡Z D”PZi DòZvi e¯‘‡Z
Zv‡ci ¯’vbvšÍi m¤¢e bq|
cøv‡¼i wee„wZ: Ggb †Kvb BwÄb ˆZix m¤¢e bq, †hUv †Kvb e¯‘ †_‡K Zvc MÖnY K‡i Aweivgfv‡e Kv‡R cwiYZ Ki‡e A_P
cwi‡e‡ki †Kvb cwieZ©b n‡e bv|
‡Kjwf‡bi wee„wZ: ‡Kvb e¯‘‡K Gi cwicv‡k¦©i kxZjZg Ask n‡Z AwaKZi kxZj K‡i kw³i Aweivg mieivn cvIqv
m¤¢e bq|
Bwćbi Zvcxq `ÿZv (Efficiency of a Engine): ‡Kvb Zvc BwÄb Øviv Kv‡R iƒcvšÍwiZ Zvc kw³i cwigvb Ges BwÄb
Øviv †kvwlZ Zvc kw³i AbycvZ‡K Bwćbi Zvcxq `ÿZv e‡j| G‡K Øviv cÖKvk Kiv nq| msÁv g‡Z,
Zvcxq `ÿZv,
kw³ Zvc kvwlZ† Øviv BwÄb
kw³ Zvc Øviv BwÄb iƒcvšÍwiZ
e¨vL¨v t †Kvb BwÄb hw` T1 ZvcgvÎvq Zvc Drm ‡_‡K Q1 Zvc ‡kvlY K‡i Ges T2 ZvcgvÎvq Q2 Zvc eR©b K‡i, Zvn‡j
BwÄb Øviv Kv‡R iƒcvšÍwiZ Zvc kw³i cwigvb = (Q1-Q2)|
1
21
QQQ
| Bwćbi Zvcxq `ÿZv‡K kZKivq cÖKvk Ki‡j Zvcxq `ÿZvi ivwkgvjv n‡e,
% 1001
21
Q
QQ % 100 1
2
1
1
ev,
% 1001 1
2
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01| Zvc MwZwe`¨v (Thermodynamics) 12
Zvc ZvcgvÎvi mgvbycvwZK, A_©vr, 11 TQ Ges 22 TQ d‡j, % 10011
2
TT
K‡Y©vi BwÄb (Carnot's Engine): Zvckw³‡K hvwš¿K kw³‡Z iƒcvšÍwiZ Kivi Rb¨ mv`x K‡b©v mKj †`vlΤœwU gy³ †h
Av`k© h‡š¿i Kíbv K‡ib Zv‡K K‡b©v BwÄb e‡j|
K‡b©v BwÄb GKwU Av`k© Bwćbi aviYvgvÎ, ev¯Í‡e Gi iƒcvšÍi m¤¢e nqwb| K‡b©v Bwćbi PviwU Ask| Ask PviwU (1)
wmwjÛvi (2) ZvcDrm (3) Zvc MÖvnK (4) Zvc AšÍiK e¯‘ ; wb‡¤œ wPÎmn wewfbœ Ask eY©bv Kiv nj|
wmwjÛvi (Cylinder): GKwU wmwjÛvi C| wmwjÛviwUi †`Iqvj m¤ú~Y© Zvc AšÍiK c`v_© Ges Zj‡`k m¤ú~yY© Zvc cwievnK
c`v_© Øviv ˆZix| Gi wfZ‡i m¤ú~Y© Zvc AšÍiK c`v‡_© ˆZix GKwU wc÷b P Nl©Ynxbfv‡e PjvPj Ki‡Z cv‡i| wmwjÛv‡ii
wfZi Kvh©wbe©vnK e¯‘ wn‡m‡e Av`k© M¨vm †bqv nq|
ZvcDrm: D”P Zvc aviYÿgZv m¤úbœ GKwU DËß e¯‘ hv T1 ZvcgvÎvq Av‡Q Ges Zv‡ci Drm wn‡m‡e KvR K‡i| Gi
ZvcgvÎv me© v w¯’i _v‡K, Zv‡ci Av`vb cÖ v‡b ZvcgvÎv KL‡bv cwieZ©b nq bv|
Zvc MÖvnK: D”P Zvc aviYÿgZv m¤úbœ T2 ZvcgvÎvq GKwU kxZj e¯‘ hv Zvc MÖvnK wn‡m‡e KvR K‡i| Gi ZvcgvÎvI
me© v w¯’i _v‡K, Zv‡ci Av`vb cÖ v‡b ZvcgvÎv KL‡bv cwieZ©b nq bv|
Zvc AšÍiK e¯‘: m¤ú~Y© Zvc AšÍiK c`v‡_©i ˆZix GKwU Avmb hvi Dci wmwjÛviwU emvb _v‡K|
K‡b©vi Pµ (Carnot's Cycle): †h we‡kl cÖwµqvq KvR Ki‡j GKwU Av`k© Zvc BwÄb Z_v K‡b©v BwÄb Aweivg kw³
mieivn Ki‡Z cv‡i Zv‡K K‡b©v Pµ e‡j| K‡b©v P‡µ cÖZ¨vMvgx cÖwµqvi gva¨‡g Kvh©wbe©vnK e¯‘ Drm †_‡K Zvc MÖnb K‡i
GKwU wbw ©ó Pvc, AvqZb I ZvcgvÎv n‡Z Avi¤¢ K‡i GKwU m‡gvò cÖmviY I GKwU iæ×Zvcxq cÖmviY Ges GKwU m‡gvò
m‡¼vPb I GKwU iæœ×Zvcxq m‡¼vP‡bi gva¨‡g Zv‡ci wKQy Ask Kv‡R iƒcvšÍi K‡i Ges evKx Ask Zvc MÖvn‡K eR©b K‡i
Avw` Ae¯’vq wd‡i Av‡m| Av`k© M¨vm‡K PviwU ch©v‡qi g‡a¨w`‡q AwZµg Kiv‡bv nq|
cÖ_g ch©vq (First Operation): cÖ_‡g wmwjÛvi C †K Zvc Dr‡mi Dci emv‡bv
nq| Lye Aímg‡qi g‡a¨ wmwjÛv‡i Ave× M¨v‡mi ZvcgvÎv Dr‡mi ZvcgvÎvi mgvb
nq|aiv hvK, GB Ae¯’vq M¨v‡mi Pvc I AvqZb h_vµ‡g P1I V1 nq hv wb‡ ©kK
wP‡Îi A we› y Øviv wb‡ ©k Kiv n‡q‡Q| GLb Av`k© M¨vm‡K m‡gvò cÖwµqvq
cÖmvwiZ n‡Z w`‡j cÖwµqv †k‡l Gi Pvc I AvqZb h_vµ‡g P2I V2 nq hv
wb‡ ©kK wP‡Îi B we› y Øviv wb‡ ©k Kiv n‡q‡Q| AB †iLv Øviv M¨v‡mi m‡gvò
cÖmviY †`Lv‡bv n‡q‡Q Ges K…Z KvR, W1=ABGE †ÿ‡Îi †ÿÎd‡ji mgvb|
wØZxq ch©vq (Second Operation): Gevi wmwjÛvi C †K Zvc-AšÍiK Avm‡bi Dci emv‡bv nq Ges Ave× M¨vm‡K
iæ×Zvcxq fv‡e cÖmvwiZ n‡Z †`Iqv nq| cÖwµqv †k‡l M¨v‡mi Pvc I AvqZb h_vµ‡g P3I V3 nq hv wb‡ ©kK wP‡Îi C
we› y Øviv wb‡ ©k Kiv n‡q‡Q| iæ× Zvcxq cÖmvi‡Yi d‡j M¨v‡mi ZvcmvÎv n«vm †c‡q Zvc MÖvn‡Ki ZvcgvÎv T2 Gi mgvb
nq| wP‡Î BC †iLv Øviv M¨v‡mi iæ× Zvcxq cÖmviY †`Lv‡bv n‡q‡Q Ges GB cÖmvi‡Y K…Z KvR, W2=BCHG †ÿ‡Îi
†ÿÎd‡ji mgvb|
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01| Zvc MwZwe`¨v (Thermodynamics) 13Z…Zxq ch©vq (Third Operation): Gevi wmwjÛvi C †K ZvcMÖvn‡Ki Dci ewm‡q Avevi M¨v‡mi Pvc e„w× Ki‡j wcób
Øviv M¨v‡mi Dci KvR m¤úvw`Z n‡e| d‡j M¨v‡mi AšÍt¯’ kw³ e„w× cv‡e| wKš‘ Ave× M¨vm e„w× cÖvß AšÍt¯’ kw³
Zvciƒ‡c ZvcMÖvn‡K eR©b K‡i ZvcgvÎv ZvcMÖvn‡Ki mgvb A_©vr T2 eRvq ivL‡e| GB Ae ’vq Ave× M¨v‡mi Pvc I
AvqZb h_vµ‡g P4 I V4 nq hv wb‡ ©kK wP‡Îi D we› y Øviv wb‡ ©k Kiv n‡q‡Q| wP‡Î CD †iLv m‡gvò ms‡KvPb wb‡ ©k
K‡i Ges GB m‡¼vP‡bi d‡j K…Z KvR, W3=CDFH †ÿ‡Îi †ÿÎd‡ji mgvb|
PZz_© ch©vq (Fourth Operation): ‡kl ch©v‡q wmwjÛvi C †K cybivq Zvc-AšÍiK Avm‡bi Dci emv‡bv nq Ges
iæ×Zvcxqfv‡e Ave× M¨v‡mi Dci Pvc evov‡bv nq| d‡j Gi AvqZb n«vm cvq| Ave× M¨v‡mi Dci KvR m¤úvw`Z
nIqvq Gi ZvcgvÎv e„wׇc‡q cybivq Dr‡mi ZvcgvÎv T1 Gi mgvb nq| GB Ae ’vh M¨v‡mi Pvc I AvqZb cybivq
h_vµ‡g P1 I V1 nq hv wb‡ ©kK wP‡Îi A we› y wb‡ ©k K‡i A_©vr Ave× M¨vm Avw` Ae¯’vq wd‡i Av‡m| wP‡Î DA †iLv
Ave× M¨v‡mi iæ× Zvcxq m‡¼vPb †`Lv‡bv n‡q‡Q d‡j K…Z KvR, W4=DAEF †ÿ‡Îi †ÿÎd‡ji mgvb|
GLv‡b W1 I W2 Ave× M¨vm Øviv K…Z KvR e‡j abvZ¥K n‡e Ges W3 I W4 Ave× M¨v‡mi Dci K…Z KvR e‡j FbvZ¥K
n‡e| d‡j Ave× e¯‘ Øviv †gvU K…Z KvR,
W= W1+ W2 - W3 - W4
W= ABGE + BCHG - CDFH - DAEF W= ABCD †ÿ‡Îi †ÿÎd‡ji mgvb| myZivs GKwU K‡b©v P‡µ Kvh©wbe©vnK e¯‘ Øviv m¤úvw`Z KvR wb‡ ©kK wP‡Î ywU
m‡gvò †iLv I ywU iæ×Zvcxq †iLv Øviv Ave× †ÿ‡Îi †ÿÎd‡ji mgvb|
GbUªwc (Entropy): ‡Kvb wm‡÷‡g kw³ _vK‡jB †h Zv‡K cÖ‡qvRbxq Kv‡R jvMv‡bv hv‡e Ggb †Kvb wbðqZv †bB| GUv
wbf©i K‡i wm‡÷‡gi ZvrÿwYK Ae¯’vi Dc‡i| Avgiv Rvwb †Kvb M¨vm‡K iæ×Zvcxq cÖwµqvq m¼zwPZ Ki‡j M¨v‡mi Dci
†h KvR Kiv nq Zvi d‡j M¨v‡mi Aš’t¯’kw³ I ZvcgvÎv †e‡o hvq| Avevi iæ×Zvcxq cÖwµqvq †Kvb M¨vm‡K cÖmvwiZ
n‡Z w`‡j M¨vm‡K wKQy KvR Ki‡Z nq| d‡j M¨v‡mi Aš’t¯’kw³ I ZvcgvÎv K‡g hvq| myZivs †`Lv hvq †h, iæ×Zvcxq
cÖwµqvq M¨v‡mi AšÍt¯’kw³ I ZvcgvÎv Df‡qiB cwieZ©b nq| wKš‘ m‡gvò cÖwµqvq †hgb ZvcgvÎv w¯’i _v‡K iæ×Zvcxq
cÖwµqvq †Zgwb †Kvb GKwU ivwk w¯’i _v‡K| K¬wmqvm GB ivwkwUi bvg †`b GbUªwc| iæ×Zvcxq cÖwµqvq e¯‘i †h Zvcxq
ag© w¯’i _v‡K Zv‡K GbUªwc e‡j| GbUªwc GKwU †fŠZ ivwk, G‡K S Øviv cÖKvk Kiv nq|
hw` †Kvb wm‡÷g T ZvcgvÎvq dQ cwigvb Zvc MÖnY ev eR©b Kivi d‡j GbUªwci cwieZ©b ds nq Z‡e
TdQds n‡e|
‡Kvb wm‡÷‡gi kw³ iƒcvšÍ‡ii AÿgZv ev Am¤¢ve¨Zv‡K ev iƒcvšÍ‡ii Rb¨ kw³i AcÖvßZv‡K GbUªwc e‡j|
GbUªwci e¨vL¨v nj e ‘i iæ×Zvcxq cÖwµqvq GbUªwc w¯’i _v‡K:
†Kvb e¯‘i GbUªÖwci cig gvb AvRI Rvbv m¤¢e nqwb| Z‡e †Kvb e¯‘ hw` Zvc MÖnb ev eR©b K‡i, Zvn‡j e¯‘i GbUªwci
cwieZ©b nq| †Kvb wm‡÷‡gi ZvcgvÎv mv‡c‡ÿ M„nxZ ev ewR©Z Zvc cwieZ©‡bi nvi Øviv GbUªwci cwieZ©b cwigvc Kiv
nq|
hw` †Kvb wm‡÷g T ZvcgvÎvq dQ cwigvb Zvc MÖnY ev eR©b Kivi d‡j GbUªwci cwieZ©b ds nq Z‡e
TdQds n‡e|
Dc‡iv³ mgxKiY n‡Z †`Lv hvq †h, iæ×Zvcxq cÖwµqvq †h‡nZz Kvh©wbe©vnK e¯‘i mv‡_ evB‡ii Zv‡ci †Kvb Av`vb cÖ vb
nqbv Kv‡RB, dQ=0 | myZivs iæ×Zvcxq cÖwµqvq GbUªwci cwieZ©b, 00
TTdQdS A_©vr iæ×Zvcxq cÖwµqvq
GbUªwci cwieZ©b nq bv A_©vr iæ×Zvcxq cÖwµqvq GbUªwci w¯’i _v‡K| myZivs †Kvb e¯‘i GbUªwc ej‡Z Avgiv Ggb GKUv
‡fŠZ ivwk‡K eywS hv e¯‘i iæ×Zvcxq cÖZ¨vMvgx cÖwµqvq me© v w¯’i _v‡K| GbUªwci cwieZ©‡bi GKK JK-1 |
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01| Zvc MwZwe`¨v (Thermodynamics) 14cÖZ¨veZ©x cÖwµqvq GbUªwc w¯’i _v‡K I AcÖZ¨veZ©x cÖwµqvq GbUªwc e„w× cvq t
cÖZ¨veZ©x cÖwµqvq GbUªwc w¯’i _v‡K:
K‡b©vi Pµ GKwU cÖZ¨veZ©x cÖwµqv| G‡Z ywU m‡gvò †iLv I ywU iæ×Zvcxq †iLv Øviv m„ó AB I CD ywU m‡gvò †iLv
Ges BC I DA ywU iæ× Zvcxq †iLv| ‡h‡nZz iæ×Zvcxq cÖwµqvq GbUªwc w¯’i _v‡K myZivs m‡gvò AB I CD Gi †ÿ‡Î
GbUªwci cwieZ©b NU‡e|
AB Gi †ÿ‡Î Zvc 1Q I ZvcgvÎv 1T n‡j GbUªwci cwieZ©b,
1
11 T
Qds
Ges CD Gi †ÿ‡Î Zvc 2Q I ZvcgvÎv 2T n‡j GbUªwci cwieZ©b,
2
22 T
Qds
†gvU GbUªwci cwieZ©b
2
2
1
121 T
QTQdsdsds
wKš‘ cÖZ¨vMvgx cÖwµqvq K‡b©vP‡µ,
2
2
1
1
TQ
TQ
G‡ÿ‡Î †gvU GbUªwci cwieZ©b, 02
2
1
121
TQ
TQdsdsds A_©vr cÖZ¨veZ©x cÖwµqvq GbUªwci cwieZ©b k~b¨|
myZivs cÖZ¨veZ©x cÖwµqvq GbUªwc w¯’i _v‡K|
AcÖZ¨veZ©x cÖwµqvq GbUªwc e„w× cvq:
aiv hvK, ywU e¯Íy A I B cwicv‡k¦©i cÖfve †_‡K gy³ Ae¯’vq ci¯ú‡ii ms¯ú‡k© Av‡Q| e¯‘Øq Ges G‡`i ms‡hvM¯’j Zvc
mycwievnx| e ‘؇qi ZvcgvÎv h_vµ‡g 1T I ;2T ;21 TT Zvc DËß e¯‘ †_‡K kxZj e¯‘‡Z mÂvwjZ n‡e| †m Zvc Avi DËß
e¯‘‡Z wd‡i Avm‡e bv| AZGe GwU GKwU AcÖZ¨veZ©x cÖwµqv|
awi, AwZ Aí mg‡q dQ cwigvb Zvc A †_‡K B †Z mÂvwjZ nq| A e¯‘ dQ cwigvb Zvc nvivq, B
e¯‘ dQ cwigvb Zvc AR©b K‡i| A e¯‘i GbUªwc n«vm ;1T
dQ B e¯‘i GbUªwc e„w× ;
2TdQ
mgMÖ e¨e¯’vq †gvU GbUªwci cwieZ©b,
12 TdQ
TdQds
G‡ÿ‡Î, †gvU GbUªwci cwieZ©b GKwU abvZ¥K ivwk; KviY, 21 TT |
AZGe, AcÖZ¨veZ©x cÖwµqvq GbUªwc e„w× cvq| A_ev Ab¨fv‡e ejv hvq,
¯ZtùzZ© cÖwµqv †mw`‡KB msNwUZ nq †h w`‡K GbUªwc e„w× cvq|
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