1. XvKv †evW©-2016 - WordPress.com...2017/03/02  · c`v_©weÁvb wØZxq cÎ: m„Rbkxj...

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c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœ i mgvavb c`v^Æweævb 1. XvKv †evW©-2016 1 bs cÖ‡kœi DËi K mymsMZ Drm n‡Z Drcbœ †Kv‡bv Zi‡½i mÂvi‡Yi Awfgy‡L †h †iLv ev Zj eivei me¸‡jv KYv mg`kvm¤úbœ Zv‡K H Zi‡½i Zi½ gyL e‡j| L Kv‡P Av‡jvK ermi 6.2710 12 km ej‡Z eySvq KvP gva¨‡g Av‡jv GK eQ‡i 6.2710 12 km `~iZ¡ AwZµg Ki‡e| M Awfj‡ÿ¨i †ÿ‡Î: †j‡Ýi †dvKvm `~iZ¡, f0 = 0.02m = 2cm e¯‘i `~iZ¡, u0 = 0.24m = 24 cm wZwe‡¤^i `~iZ¡ v0 n‡j, 1 v0 + 1 u0 = 1 f0 ev, 1 v0 = 1 f0 1 u0 = 1 2 1 24 = 11 24 v0 = 2.1818 cm. Awf‡b‡Îi †ÿ‡Î: †dvKvm `~iZ¡, fe = 0.05 m = 5 cm G‡ÿ‡Î, cÖwZwe¤^wU Awfj‡ÿ¨i †cQ‡b wKš‘ Awf‡b‡Îi mvg‡b MwVZ nIqvq cÖwZwe¤^wU Awf‡b‡Îi Rb¨ Aev¯Íe| wZwe‡¤^i `~iZ¡, ve = – 0.12 m = – 12 cm e¯‘i `~iZ¡ ue n‡j, 1 ue + 1 ve = 1 fe ev, 1 ue = 1 fe 1 ve = 1 5 + 1 12 = 17 60 ue = 3.529 cm ¿wUi ˆ`N© ¨, L = v0 + ue = (2.1818 + 3.529) cm = 5.7108 cm (Ans.) N †jÝØq Ae¯’vb cwieZ©‡bi Av‡M weea©‡bi ivwkgvjv: GLv‡b, Awf‡bÎ Øviv m„ó P‚ovšÍ we‡¤^i `~iZ¡, v2 = – 25 cm [†h‡nZz ¯úó `k©‡bi b~¨bZg `~i‡Z¡ †dvKvm Kiv nq] Awf‡b‡Îi †dvKvm `~iZ¡, fe = 0.05m = 5 cm awi, Awf‡b‡Îi jÿ¨e¯‘i `~iZ¡, ue = ? Avgiv Rvwb, 1 ue + 1 ve = 1 fe ev, 1 ue = 1 fe 1 ve = 1 5cm + 1 25cm ue = 4.17cm Avevi, Awfj‡ÿ¨i †dvKvm `~iZ¡, fo = 0.02m = 2 cm b‡ji ˆ`N© ¨, L = 5.7108cm Awfj‡ÿ¨i we‡¤^i `~iZ¡, vo = L – ue = (5.7108 – 4.17) cm = 1.5408 cm Awfjÿ¨ †_‡K e¯‘i `~iZ¡, uo = ? GLb, 1 uo + 1 vo = 1 fo ev, 1 uo = 1 fo 1 vo = 1 2 cm 1 1.5408 cm uo = – 0.15 cm myZivs hš¿wUi weea©b, mm = vo uo 1 + D fe = – 1.5408 0.15 1 + 25 5 = 61.632 |mm| = 61.632 †jÝØq Ae¯’vb cwieZ©‡bi ci weea©‡bi ivwkgvjv : G‡ÿ‡Î, Awfj‡ÿ¨i †dvKvm `~iZ¡, fo = 5 cm Awf‡b‡Îi †dvKvm `~iZ¡, fe = 2 cm G‡ÿ‡Î, hš¿wU `~iexÿY hš¿ wn‡m‡e KvR Ki‡e| weea©b, mT = fo fe 1 + fe D = 5 2 1 + 2 25 = 2.7 |mT| = 2.7 < |mm| †jÝØq Ae¯’vb cwieZ©‡bi ci weea©b K‡g hv‡e| 2 bs cÖ‡kœi DËi K `ywU PvwR©Z e¯‘i AvKvi hw` Zv‡`i ga¨eZ©x `~i‡Z¡i Zzjbvq Lye †QvU nq Z‡e Zv‡`i‡K we›`y PvR© ejv nq| L †Kv‡bv PvwR©Z cwievnx †Mvj‡Ki Af¨šÍ‡i †Kv‡bv PvR© _v‡K bv, mg¯Í PvR© Ae¯’vb K‡i Gi c„‡ô| Zwor ej †iLv wbM©Z nq PvR© †_‡K, ZvB ejv hvq PvwR©Z †MvjvKvi cwievnxi Af¨šÍ‡i †Kv‡bv ej †iLv _v‡K bv| ZvB PvwR©Z †Mvj‡Ki Af¨šÍ‡i †Kvb wefe cv_©K¨I _v‡K bv A_©vr cÖ‡Z¨K we›`yi wefe mgvb _v‡K| GRb¨ PvwR©Z cwievnx †Mvj‡Ki †K‡›`ª cÖvej¨ k~b¨ nq| M Avgiv Rvwb, avi‡K mwÂZ kw³, GLv‡b, http://teachingbd.com Teachingbd.com

Transcript of 1. XvKv †evW©-2016 - WordPress.com...2017/03/02  · c`v_©weÁvb wØZxq cÎ: m„Rbkxj...

  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    1. XvKv †evW©-2016

    1 bs cÖ‡kœi DËi

    K mymsMZ Drm n‡Z Drcbœ †Kv‡bv Zi‡½i mÂvi‡Yi Awfgy‡L †h †iLv ev Zj eivei me¸‡jv KYv mg`kvm¤úbœ Zv‡K H Zi‡½i

    Zi½ gyL e‡j|

    L Kv‡P Av‡jvK ermi 6.271012 km ej‡Z eySvq KvP gva¨‡g Av‡jv GK eQ‡i 6.271012 km ~̀iZ¡ AwZµg Ki‡e|

    M Awfj‡ÿ¨i †ÿ‡Î: †j‡Ýi †dvKvm ~̀iZ¡, f0 = 0.02m = 2cm

    e¯‘i ~̀iZ¡, u0 = 0.24m = 24 cm

    cÖwZwe‡¤^i `~iZ¡ v0 n‡j,

    1v0

    + 1u0

    = 1f0

    ev, 1v0

    = 1f0

    – 1u0

    = 12 –

    124 =

    1124

    v0 = 2.1818 cm.

    Awf‡b‡Îi †ÿ‡Î: †dvKvm ~̀iZ¡, fe = 0.05 m = 5 cm

    G‡ÿ‡Î, cÖwZwe¤^wU Awfj‡ÿ¨i †cQ‡b wKš‘ Awf‡b‡Îi mvg‡b MwVZ

    nIqvq cÖwZwe¤^wU Awf‡b‡Îi Rb¨ Aev Í̄e|

    cÖwZwe‡¤^i ~̀iZ¡, ve = – 0.12 m = – 12 cm

    e¯‘i ~̀iZ¡ ue n‡j,

    1ue

    + 1ve

    = 1fe

    ev, 1ue

    = 1fe

    – 1ve

    = 15 +

    112 =

    1760

    ue = 3.529 cm

    hš¿wUi ˆ`N©̈ , L = v0 + ue = (2.1818 + 3.529) cm

    = 5.7108 cm (Ans.)

    N †jÝØq Ae¯’vb cwieZ©‡bi Av‡M weea©‡bi ivwkgvjv:

    GLv‡b,

    Awf‡bÎ Øviv m„ó P‚ovšÍ we‡¤^i ~̀iZ¡, v2 = – 25 cm

    [†h‡nZz ¯úó `k©‡bi b~¨bZg `~i‡Z¡ †dvKvm Kiv nq]

    Awf‡b‡Îi †dvKvm ~̀iZ¡, fe = 0.05m = 5 cm

    awi, Awf‡b‡Îi jÿ¨e ‘̄i ~̀iZ¡, ue = ?

    Avgiv Rvwb, 1ue

    + 1ve

    = 1fe

    ev, 1ue

    = 1fe

    – 1ve

    = 1

    5cm + 1

    25cm

    ue = 4.17cm

    Avevi, Awfj‡ÿ¨i †dvKvm ~̀iZ¡, fo = 0.02m = 2 cm

    b‡ji ˆ`N©̈ , L = 5.7108cm

    Awfj‡ÿ¨i we‡¤^i ~̀iZ¡, vo = L – ue

    = (5.7108 – 4.17) cm

    = 1.5408 cm

    Awfjÿ¨ †_‡K e ‘̄i ~̀iZ¡, uo = ?

    GLb, 1uo

    + 1vo

    = 1fo

    ev, 1uo

    = 1fo

    – 1vo

    = 1

    2 cm – 1

    1.5408 cm

    uo = – 0.15 cm

    myZivs hš¿wUi weea©b, mm = –vouo

    1 +

    Dfe

    = – 1.5408

    0.15

    1 +

    255 = 61.632

    |mm| = 61.632

    †jÝØq Ae¯’vb cwieZ©‡bi ci weea©‡bi ivwkgvjv :

    G‡ÿ‡Î, Awfj‡ÿ¨i †dvKvm ~̀iZ¡, fo = 5 cm

    Awf‡b‡Îi †dvKvm ~̀iZ¡, fe = 2 cm

    G‡ÿ‡Î, hš¿wU `~iexÿY hš¿ wn‡m‡e KvR Ki‡e|

    weea©b, mT = fofe

    1 +

    feD =

    52

    1 +

    225 = 2.7

    |mT| = 2.7 < |mm|

    †jÝØq Ae¯’vb cwieZ©‡bi ci weea©b K‡g hv‡e|

    2 bs cÖ‡kœi DËi

    K ỳwU PvwR©Z e ‘̄i AvKvi hw` Zv‡`i ga¨eZ©x ~̀i‡Z¡i Zzjbvq Lye †QvU nq Z‡e Zv‡`i‡K we› ỳ PvR© ejv nq|

    L †Kv‡bv PvwR©Z cwievnx †Mvj‡Ki Af¨šÍ‡i †Kv‡bv PvR© _v‡K bv, mg¯Í PvR© Ae¯’vb K‡i Gi c„‡ô| Zwor ej †iLv wbM©Z nq PvR©

    †_‡K, ZvB ejv hvq PvwR©Z †MvjvKvi cwievnxi Af¨šÍ‡i †Kv‡bv ej

    †iLv _v‡K bv| ZvB PvwR©Z †Mvj‡Ki Af¨šÍ‡i †Kvb wefe cv_©K¨I

    _v‡K bv A_©vr cÖ‡Z¨K we› ỳi wefe mgvb _v‡K| GRb¨ PvwR©Z

    cwievnx †Mvj‡Ki †K‡›`ª cÖvej¨ k~b¨ nq|

    M Avgiv Rvwb, avi‡K mwÂZ kw³,

    GLv‡b,

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    U = 12 QV

    = 12 2 C 2 V

    Pv‡R©i cwigvY, Q = 2 C

    cvZ؇qi wefe cv_©K¨, V = 2 V

    mwÂZ kw³, U = ?

    = 2 J

    AZGe, wPÎ (i) Gi avi‡Ki mwÂZ kw³ 2J. (Ans.)

    N GLv‡b, wPÎ (i)Gi avi‡Ki–

    cv‡Zi †ÿÎdj, A1 = 4 cm2

    awi, cvZ؇qi ga¨eZ©x ~̀iZ¡ = d1

    Ges wPÎ (ii)Gi avi‡Ki-

    cv‡Zi †ÿÎdj, A2 = 2 cm2

    awi, cvZ؇qi ga¨eZ©x ~̀iZ¡ = d2

    myZivs cÖ_g avi‡Ki aviKZ¡, C1 = A10K

    d1

    Ges wØZxq avi‡Ki aviKZ¡, C2 = A20K

    d2

    kZ©vbymv‡i, Dfq avi‡Ki aviKZ¡ mgvb n‡Z n‡e

    A10K

    d1 =

    A20Kd2

    ev, d1d2

    = A1A2

    = 4 cm2

    2 cm2 = 2

    ev, d1 = 2d2

    MvwYwZK we‡kølY †_‡K †`Lv hvq, 1g avi‡Ki cvZ؇qi ga¨eZ©x

    `~iZ¡ wØZxq avi‡Ki cvZ؇qi ga¨eZ©x ~̀i‡Z¡i wظY Kiv n‡j, D³

    aviK؇qi aviK‡Z¡i gvb mgvb n‡e|

    myZivs wPÎ (i) I (ii) Gi aviK ỳwUi cvZ؇qi ga¨eZ©x ~̀i‡Z¡i

    AbycvZ 2 t 1 n‡j Dfq avi‡Ki aviKZ¡ mgvb n‡e|

    3 bs cÖ‡kœi DËi

    K GKwU gvÎ eZ©bx‡Z Zwor cÖev‡ni cwieZ©‡bi d‡j A_ev †Kv‡bv †PŠ¤^K‡ÿ‡Î eZ©bxi MwZi d‡j eZ©bxi mv‡_ mswkøó †PŠ¤^K d¬v‡·i

    cwieZ©‡bi Rb¨ †h Zwor †PŠ¤^K Av‡ek N‡U Zv‡K ¯̂Kxq Av‡ek

    e‡j|

    L Pz¤^‡Ki †PŠ¤̂K †ÿ‡Îi cÖfve‡K Kv‡R jvwM‡q ˆe ỳ¨wZK kw³ ˆZwi Kiv hvq| GKwU e× KzÛjxi mv‡_ GKwU M¨vjfv‡bvwgUvi hy³

    K‡i GKwU Pz¤^K `ЇK KzÐjxi mv‡c‡ÿ MwZkxj Kiv n‡j Gi mv‡_

    hy³ M¨vjfv‡bvwgUviwU wewÿß n‡Z †`Lv hvq| G †_‡K †evSv hvq

    MwZkxj Pz¤^K e× KzÐjx‡Z Zwor cÖevn m„wó K‡i|

    M Avgiv Rvwb, ZwoZevnx j¤̂v †mvRv Zv‡ii Avkcv‡ki †Kv‡bv we›`y‡Z m„ó †PŠ¤^K †ÿ‡Îi gvb,

    B = μ0I2πa

    B = (4π 10–7) (5 A)

    2π 0.5 m

    GLv‡b, Zwor cÖevn, I = 5A

    Zvi n‡Z C we› ỳ‡Z ̀ ~iZ¡, a = 0.5m

    †PŠ¤^K †ÿÎ, B = ?

    = 210–6 T

    = 2 μT (Ans.)

    N †d¬wgs‡qi Wvb n Í̄ wbqgvbymv‡i AB Zv‡i Zwor cÖev‡ni Rb¨ Y we›`y‡Z m„ó †PŠ¤̂K †ÿ‡Îi w`K n‡e KvMR Z‡ji mv‡_ j¤̂ eivei

    wfZ‡ii w`‡K| †d¬wgs‡qi evg n Í̄ wbqgvbymv‡i Y we› ỳ‡Z Zworevnx

    CD Zv‡ii Dci †PŠ¤̂K e‡ji w`K n‡e CD Zv‡ii Dci j¤̂ Ges AB

    †h w`‡K Av‡Q Zvi wecixZ w`‡K|

    Avevi †d¬wgs‡qi Wvb n¯Í wbqgvbymv‡i CD Zv‡i Zwor cÖev‡ni Rb¨

    X we›`y‡Z m„ó †PŠ¤^K †ÿ‡Îi w`K n‡e KvMR Z‡ji mv‡_ j¤̂ eivei

    wfZ‡ii w`‡K| †d¬wgs‡qi evg n¯Í wbqgvbymv‡i X we›`y‡Z Zworevnx

    AB Zv‡ii Dci †PŠ¤̂K e‡ji w`K n‡e AB Zv‡ii Dci j¤̂ Ges CD

    †h w`‡K Av‡Q Zvi wecixZ w`‡K|

    X I Y we›`y‡Z Zv‡ii Dci wµqvkxj ej؇qi w`‡K †_‡K †evSv hvq

    ZviØq ci¯úi‡K weKl©Y Ki‡e|

    4 bs cÖ‡kœi DËi

    K ci¯ú‡ii mv‡c‡ÿ aªæe †e‡M MwZkxj †h mKj cÖm½ KvVv‡gv‡Z wbDU‡bi MwZ m~θ‡jv AR©b Kiv hvq, Zv‡`i‡K Ro cÖm½ KvVv‡gv

    e‡j|

    L wbw`©ó avZzi c„ô n‡Z B‡jKUªb‡K gy³ Ki‡Z GKwU b~¨bZg kw³i cÖ‡qvRb hv‡K Kv‡h©v‡cÿK e‡j| Av‡jvK Zwor wµqvi

    †Kvqv›Uvg ZË¡vbymv‡i GB b~¨bZg kw³i mieiv‡ni Rb¨ GKwU

    b~¨bZg K¤úvs‡Ki Av‡jv cÖ‡qvRb hvi †P‡q Kg K¤úvsK wewkó

    Av‡jv avZzi Kv‡h©v‡cÿ‡Ki mggv‡bi kw³ B‡jKUªb‡K mieivn

    Ki‡Z cv‡i bv| GB K¤úvsKB n‡jv m~Pb K¤úvsK| m~Pb K¤úvsK

    hZ Kg nq| wbw ©̀ó e‡Y©i I ZxeªZvi Av‡jvi Rb¨ (e„nËi K¤úvsK)

    avZzi d‡Uv B‡jKUª‡bi †eM ZZ ev‡o d‡j Av‡jvK Zwor Gi gvbI

    ev‡o| m~Pb K¤úvsK hZ e„w× cvq, Av‡jvK kw³i ZZ †ewk Ask

    B‡jKUªb‡K gy³ Ki‡Z e¨q nq| ZvB d‡Uv Zwor Gi gvb I K‡g

    hvq| A_v©r avZzi Av‡jvK Zwor wµqv Gi m~Pb K¤úvs‡Ki Dci

    wbf©ikxj|

    M wPÎ (i) Abymv‡i B‡jKUªbwU cÖ_g Kÿc‡_ Av‡Q| Avgiv Rvwb, nvB‡Wªv‡Rb cigvYyi n-Zg Kÿc‡_i e¨vmva©,

    0.5 m

    B A

    C D

    X

    Y

    5 A

    5 A

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    2

    0

    22

    me

    hnrn

    GLv‡b, n = 1

    0 = 8.85 10 – 12 C2 N– 1 m– 2

    B‡jKUª‡bi fi, m = 9.1 10 – 31 kg

    B‡jKUª‡bi PvR©, e = 1.6 10 – 19 C

    cø̈ v‡¼i aªyeK, h = 6.63 10 – 34 J s

    Kÿc‡_i e¨vmva©, rn = r1 = ?

    myZivs, cÖ_g Kÿc‡_i e¨vmva©,

    21931

    212122342

    1)C 106.1)(kg 101.9)(14.3(

    )mNC 1085.8()sJ 1063.6)(1(

    r

    = 0.53 10 – 10 m = 0.53 Å (Ans.)

    N n I (n + 1) Zg Kÿc‡_ kw³i e¨eavb,

    E = me4

    8h202

    1

    n2 – 1

    (n + 1)2

    me©vwaK Zi½‰`N©¨ max n‡j, B‡jKUªb‡K KÿPz¨Z Ki‡Z cÖ‡qvRbxq kw³

    hc

    max =

    me4

    8e202

    1

    n2 – 1

    (n + 1)2

    ev, max = 8h302C

    me4 1

    1n2 –

    1(n + 1)2

    ev, max = 8h302C

    me4 1

    11 –

    122

    ev, max= 8 (6.63 10–34)3 (8.85 10–12)2 3 108

    9.11 10–31 (1.6 10–19)4

    43

    ev, max = 1.1953 10–7m

    max = 1195.3125 Å

    DÏxc‡Ki Dfq wP‡ÎB AvewZ©Z †Kv‡Yi Zi½‰`N©¨ max Gi Zzjbvq †ewk|

    myZivs †Kvb †ÿ‡ÎB B‡jKUªb KÿPz¨Z n‡e bv|

    5 bs cÖ‡kœi DËi

    K †KvqvK© n‡jv c`v‡_©i †gŠwjK KYv I †gŠwjK cÖ‡qvRbxq Dcv`vb hv Øviv c`v_© MwVZ|

    L iƒ×Zvcxq cÖwµqvq †Kv‡bv iƒc Zv‡ci Av`vb cÖ`vb nqbv, ZvB dQ = 0| myZivs, ZvcMwZwe`¨vi cÖ_g m~Îbymv‡i,

    0 = U + W

    U = – W

    A_©vr, iƒ×Zvcxq cÖwµqvq M¨vm Zvi AšÍt¯’ kw³i wewbg‡q KvR

    K‡i| iƒ×Zvcxq cÖmvi‡Yi †ÿ‡Î wm‡÷g Øviv KvR Kiv nq e‡j

    dW abvZ¥K nq| Avi ZvB, dU = – dW mgxKiY Abymv‡i wm‡÷‡gi Af¨šÍixY kw³ n«vm cvq|

    M 1 bs eZ©bxwU GKwU AND †MB‡Ui| Gi Dfq BbcyU A_ev †h‡Kv‡bv GKwU BbcyU 0 (k~b¨) n‡jB AvDUcyU 0 (k~b¨) n‡e Ges †Kej gvÎ Dfq BbcyU 1 n‡jB AvDUcyU 1 n‡e| myZivs Gi mZ¨K mviwY n‡”Q–

    A B X 0 0 0 1 0 0 0 1 0 1 1 1

    N eywjqvb exRMwY‡Zi mvnv‡h¨ wjL‡j DÏxc‡K cÖ`Ë mZ¨K mviwYwU OR Acv‡ikb‡K mg_©b K‡i| KviY P A_ev Q A_ev DfqB 1 n‡j R = 1 nq| A_©vr P + Q = R| ZvB cÖ`Ë mviwYwU OR †MB‡Ui| wb‡P Gi eZ©bx I cÖZxK †`qv nj|

    eZ©bxwUi AvDUcy‡U GKwU NOT †MBU hy³ Ki‡j eZ©bxwU n‡e wb¤œiƒc

    GwU GKwU NOR †MBU| Gi mZ¨K mviwY n‡”Q-

    P Q R S

    0 0 0 1

    0 1 1 0

    1 0 1 0

    1 1 1 0

    6 bs cÖ‡kœi DËi

    K GKK abvZ¥K PvR©‡K eZ©bxi †Kv‡bv GK we› ỳ †_‡K Drmmn m¤c~Y© eZ©bx Nywi‡q cybivq H we› ỳ‡Z Avb‡Z †h KvR nq ev Dr‡mi

    †h kw³ e¨q nq Zv‡K Dr‡mi Zwo”PvjK ej e‡j|

    L mxmv I wU‡bi (mxmv 75% Ges wUb 25%) mswgkÖ‡Y ˆZwi GKwU miy Zvi‡K wbivcËv wdDR wn‡m‡e e¨envi Kiv nq| G Zv‡ii

    eZ©bx

    R

    P

    Q R = P + Q P

    Q

    cÖZxK

    R = P + Q

    P

    Q S = R–

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    Mjbv¼ Kg (cÖvq 300C)| Zv‡ii ga¨ w`‡q AwZwi³ Zwor cÖevwnZ n‡j ZviwU Mig n‡q D‡V Ges Zv M‡j wM‡q we ỳ¨r mieivn e›a

    K‡i †`q| g~jZ Mjbv¼ Kgvevi Rb¨ wbivcËv wdD‡R weï× avZz

    e¨envi Kiv nq bv|

    M Avgiv Rvwb, M¨vjfv‡bvwgUvi cÖevn,

    GLv‡b,

    ig = S

    G + S i

    ev, 10-2 A (G + S) = S 1 A

    ev, G + S = 100 S

    ev, 99 S = 100

    g~j cÖevn, i = 1 A

    M¨vjfv‡bvwgUvi †iva, G = 100

    M¨vjfv‡bvwgUvi cÖevn,

    ig = 10 mA = 10-2 A

    mv›U †iva, S = ?

    S = 1.01 (Ans.)

    N nviæb M¨vjfv‡bvwgUv‡ii eZ©bx m¾vi cwieZ©b ỳfv‡e Ki‡Z cv‡i

    (i) mv›UwU cwieZ©b Ki‡Z cv‡i

    mv‡›Ui gvb cwieZ©b K‡i S gv‡bi mv›U e¨venvi Ki‡j

    Avgiv Rvwb, M¨vjfv‡bvwgUvi cÖevn,

    ig = S

    G + S i

    ev, 10-2 A (G + S ) = S 10 A

    ev, G + S = 1000 S

    ev, 999 S = 100

    S = 0.1

    GLv‡b,

    g~j cÖevn, i = 10 A

    M¨vjfv‡bvwgUvi †iva, G = 100

    M¨vjfv‡bvwgUvi cÖevn,

    ig = 10 mA = 10-2 A

    mv›U †iva, S = ?

    (ii) Av‡iv GKwU mv›U e¨envi Ki‡Z cv‡i|

    cÖ̀ Ë eZ©bxi M¨vjfv‡bvwgUvi I mv›U‡K GK‡Î GKwU A¨vwgUvi

    we‡ePiv Ki‡j Gi cvjøv n‡e 1 A Ges Zzj¨ †iva n‡e,

    R = GS

    G + S = 100 1.01

    100 + 1.01 = 0.9999

    GLb A¨vwgUv‡ii cvjøv 10 A Ki‡Z n‡j G cvjøv n‡e Avw` cvjøvi 10 ¸Y

    A¨vwgUv‡ii cvjøv e„w×i m~Î †_‡K Rvwb, Gi mv‡_ hy³ mv›U †iva,

    S1 = 0.9999

    10 – 1 = 0.1111

    2. ivRkvnx †evW©-2016

    1bs cÖ‡kœi DËi

    K `ywU mgvb I wecixZ AšÍwiZ we›`y Avavb Aí ~̀i‡Z¡ Aew¯’Z _vK‡j Zv‡K Zwor w؇giæ e‡j|

    L †Kv‡bv wm‡÷‡gi G›Uªwc evovi mv‡_ mv‡_ †mLvb †_‡K KvR cvIqvi m¤¢vebv †hgb K‡g hvq †Zgwb wm‡÷‡gi wek„•LjvI e„w×

    cvq| †Kv‡bv wm‡÷‡gi Dci evB‡i †_‡K kw³ cÖ‡qvM K‡i hw`

    k„•Lj Avbvi †Póv Kiv nq Zvn‡j wm‡÷‡gi G›Uªwc K‡g hv‡e| e ‘̄

    hLb †KjvwmZ Ae ’̄vq _v‡K ZLb Aby¸‡jv mymse× myk„•Lj

    mgv‡e‡k _v‡K, †m Kvi‡Y KwVb Ae¯’vq e ‘̄i G›Uªwc Kg| myZivs

    G›Uªwc I wek„•Ljv IZ‡cÖvZfv‡e m¤úwK©Z| G Kvi‡Y ejv hvq,

    †Kv‡bv wm‡÷‡gi wek„•Ljvi m~PK cwigvc‡Ki ivwk G›Uªwc|

    M DÏxcK Abymv‡i,

    A we›`y‡Z ¯’vwcZ Avavb, q1 = 2C

    B we›`y‡Z ¯’vwcZ Avavb, q2 = 2C

    C we›`y‡Z ¯’vwcZ Avavb, q3 = 2C

    eM©‡ÿÎwUi, AB = BC = CD = DA = 1m

    wc_v‡Mviv‡mi m~Îvbyhvqx, BD2 = AB2 + AD2

    ev, BD2 = 12 + 12

    ev, BD2 = 2

    BD = 2 m

    D we› ỳ‡Z wefe, VD = 1

    4o

    q1

    AD + q2BD +

    q3CD

    = 9 109

    2

    1 + 2

    2 +

    21

    = 2.327 1010V (Ans.)

    N ÔMÕ Ask n‡Z cvB, BD = 2 m

    A we›`y‡Z ¯’vwcZ Avav‡bi Rb¨ D we›`y‡Z cÖvej¨,

    E1 = 1

    4o .

    q1AD2

    = 9 109 212

    = 1.8 1010 NC1

    Gi w`K AD eivei

    B we›`y‡Z ¯’vwcZ Avav‡bi Rb¨ D we›`y‡Z cÖvej¨,

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    E2 = 1

    4o

    q1BD2

    = 9 109 2

    ( 2)2

    = 9 109 NC1

    Gi w`K DB eivei|

    C we›`y‡Z ¯’vwcZ Avav‡bi Rb¨ D we›`y‡Z cÖvej¨,

    E3 = 1

    4o

    q3CD2

    = 9 109 212

    = 1.8 109 NC1

    Gi w`K CD eivei|

    E1 I E3 Gi ga¨eZ©x †KvY, 1 = 90

    E1 I E3 Gi jwä cÖvej¨,

    E4 = E12 + E32 + 2E1 E3 cos 90

    = (1.8 1010)2 + (1.8 1010)2 + 0

    = 2.55 1010 NC1

    E1 I E4 Gi ga¨eZ©x †KvY 1 n‡j,

    tan1 = E3 sin1

    E1 + E3 cos1

    = 1.8 109 sin 90

    1.8 109 + 1.8 109 cos 90

    = 1.8 109

    1.8 109

    ev, 1 = tan1(1)

    1 = 45

    E4 I E2 ci¯úi wecixZgyLx e‡j,

    jwä cÖvej¨, E = E4 E2

    = 2.55 1010 9 109

    = 1.65 1010 NC1

    awi, jwä cÖvej¨ E, E2 Gi mv‡_ †KvY Drcbœ K‡i|

    E4 I E2 Gi ga¨eZ©x †KvY, = 180

    tan = E4 sin

    E2 + E4 cos

    = 2.55 1010 sin 180

    9 109 + 2.55 1010 cos 180

    = 0

    9 109 2.55 1010

    = 0

    = tan1 (0) = 0

    AZGe, D we› ỳ‡Z jwä cÖvej¨ 1.65 1010 NC1 Ges Gi w`K BD eivei|

    2bs cÖ‡kœi DËi

    K †Kv‡bv Zwor †ÿ‡Î †Kv‡bv e× KwíZ Z‡ji ga¨ w`‡q AwZµvšÍ

    †gvU Zwor d¬v‡·i cwigvY H Zj Øviv mxgve× Pv‡R©i

    1

    0 ¸‡Yi

    mgvb|

    L `ywU c`v_© hLb Nl©Y Kiv nq ZLb c`v_© `ywUi g‡a¨ hvi cigvYy‡Z B‡jKUª‡bi eÜb A‡cÿvK…Z wkw_j Zv †_‡K wKQy

    B‡jKUªb wew”Qbœ n‡q AciwU‡Z P‡j hvq| Gi d‡j †h e ‘̄ †_‡K

    B‡jKUªb wew”Qbœ nq †mB e¯‘wU‡Z B‡jKUª‡bi msL¨v K‡g hvIqvq

    Zv abvZ¥K Pv‡R© PvwR©Z nq Ges Ab¨ e¯‘wU‡Z B‡jKUª‡bi AvwaK¨

    NUvq GwU FYvZ¥K Pv‡R© PvwR©Z nq| d‡j e ‘̄wU AvwnZ nq| wKš‘

    †Kv‡bv e ‘̄‡K nvZ Øviv Nl‡j e ‘̄wU AvwnZ nq bv †Kbbv nvZ †_‡K

    B‡jKUªb H e ‘̄‡Z ¯’vbvšÍwiZ nq bv|

    M DÏxcK n‡Z cvB, eZ©bxi

    †iva, R1 = 12

    †iva, R2 = 6

    †iva, R3 = 3

    wefe, V = 8V

    R2 I R3 †ivaØq mgvšÍiv‡j hy³ _vKvq Zv‡`i Zzj¨ †iva Rp n‡j,

    1Rp

    = 1R2

    + 1R3

    ev, 1Rp

    = 16 +

    13

    Rp = 2

    Avgiv Rvwb, V = I1R1

    ev, I1 = VR1

    = 8

    12 = 0.67A

    E

    D E

    E E

    C

    BA

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    Avevi, V = I2 Rp

    ev, I2 = VRp

    = 82 = 4 A

    g~j cÖevn, I = I1 + I2

    = (4 + 0.67)A

    = 4.67 A (Ans.)

    N wP‡Î D‡jøwLZ †iva¸‡jv‡K †kÖwY mgev‡q mvwR‡q AswKZ wPÎwU wb¤œiƒc n‡e:

    Zzj¨ †iva, Rs = R1 + R2 + R3

    = (12 + 6 + 3)

    = 21

    Avgiv Rvwb, V = IRs

    ev, I = VRs

    = 8

    21 = 0.38 A

    ÔMÕ Ask n‡Z cvB g~j cÖevn = 4.67A

    g~j cÖev‡ni cwieZ©b = (4.67 0.38)A

    = 4.29 A

    AZGe, wP‡Î D‡jøwLZ †iva¸‡jv‡K †kÖwY mgev‡q mvRv‡j g~j cÖevn

    4.29A n«vm cv‡e|

    3bs cÖ‡kœi DËi

    K †h †PŠ¤̂K †ÿ‡Î 1 Kzj¤^ Avavb †ÿ‡Îi w`‡Ki mv‡_ mg‡Kv‡Y 1ms1 †e‡M MwZkxj n‡j 1N ej Abyfe K‡i †mB †PŠ¤̂K †ÿ‡Îi gvb‡K 1 †Umjv e‡j|

    L ̄ ^Kxq Av‡ek ¸Yv¼ 5 †nbwi ej‡Z eySvq †Kv‡bv KzÐjx‡Z Zwor cÖevn cÖwZ †m‡K‡Û GK A¨vw¤úqvi nv‡i cwiewZ©Z n‡j D³

    KzÐjx‡Z 5 †fvë Zwo”PvjK kw³ Avweó nq|

    M †`Iqv Av‡Q,

    Kÿc‡_i e¨vmva© Z_v B‡jKUªb I †cÖvU‡bi ga¨eZ©x ~̀iZ¡, r = 5.3 1011 m

    B‡jKUª‡bi Avavb = †cÖvU‡bi Avavb = e = 1.6 1019C

    †K‡›`ª Kzj¤^ ej, Fe = ?

    Avgiv Rvwb, Fe = C e e

    r2

    = 9 109 e2

    r2

    = 9 109 (1.6 1019)2

    (5.3 1011)2

    = 8.2 108 N (Ans.)

    N DÏxcK n‡Z cvB,

    B‡jKUª‡bi ª̀æwZ, v = 2.185 106 ms1

    B‡jKUª‡bi fi, m = 9.1 1031 kg

    e„ËvKvi c‡_i e¨vmva©, r = 5.3 1011 m

    †K›`ªgyLx ej, Fc = ?

    Avgiv Rvwb, Fc = mv2

    r

    = 9.1 1031 (2.185 106)2

    5.3 1011

    = 8.2 108 N

    ÔMÕ Ask n‡Z cvB, †K‡›`ª Kzj¤^ ej, Fe = 8.2 108 N

    Avgiv Rvwb, †K› ª̀gyLx ej hLb Kzj¤^ e‡ji mgvb nq ZLb †K‡› ª̀i

    wecixZ w`‡K †K› ª̀gyLx e‡ji mgvb GKwU ej KvR K‡i hv‡K

    †K›`ªwegyLx ej ejv nq| †K› ª̀gyLx ej †K› ª̀wegyLx e‡ji mgvb n‡j

    e„ËvKvi c‡_ N~Y©vqgvb †Kvb e¯‘ Kÿc‡_B Ae ’̄vb K‡i| GLv‡b,

    Fe = Fc| Avi ZvB N~Y©biZ B‡jKUªbwU cigvYyi Kÿc_ †_‡K wQU‡K co‡e bv|

    4bs cÖ‡kœi DËi

    K †h mKj wcÖR‡gi cÖwZmviK †KvY 6-Gi †P‡q eo bq Zv‡`i‡K miæ wcÖRg e‡j|

    L AYyexÿY I ~̀iexÿY h‡š¿i MVbMZ cv_©K¨ wb‡¤œi ZvwjKvq wjwce× Kiv n‡jv:

    AYyexÿY hš¿ `~iexÿY hš¿

    1. Awfj‡ÿ¨i †dvKvm ~̀iZ¡ I

    D‡š§l A‡cÿvK…Z †QvU|

    1. Awfj‡ÿ¨i †dvKvm ~̀iZ¡ I

    D‡š§l A‡cÿvK…Z eo|

    2. Awf‡b‡Îi †dvKvm ~̀iZ¡ I

    D‡š§l A‡cÿvK…Z eo| 2. Awf‡b‡Îi †dvKvm ~̀iZ¡ I

    D‡š§l A‡cÿvK…Z †QvU|

    M DÏxcK n‡Z cvB, wP‡oi ga¨eZ©x `~iZ¡, d = 0.3mm = 0.3 103 m

    c`©vi ~̀iZ¡, D = 1m

    R1 = 12 R2 = 6 R3 = 3

    8V I

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    8g D¾¡j cwÆi `~iZ¡, x8 = 6.2 mm = 6.2 103 m

    Av‡jvi Zi½‰`N©¨, = ?

    Avgiv Rvwb, x8 = 8D

    d

    ev, = d x88 D

    = 0.3 103 6.2 103

    8 1

    = 2.32 107m (Ans.)

    N DÏxcK n‡Z cvB,

    wP‡oi ga¨eZ©x ~̀iZ¡, d = 0.3mm = 0.3 103m

    c`©vi ~̀iZ¡, D = 1 m

    cvwbi cÖwZmiv¼, w = 43

    evqyi cÖwZmiv¼, a = 1

    ÔMÕ Ask n‡Z cvB, evqy‡Z Zi½ ˆ`N©¨, a = 2.32 107m

    Avgiv Rvwb, w w = a a

    ev, w = a aw

    = 4 2.32 107

    4/3

    = 1.74 107 m

    evqy gva¨‡g cwÆ ev Svj‡ii cÖ¯’, xa = aD2d =

    2.32 107 1

    2 0.3 103

    = 386.67 106 m

    cvwbi g‡a¨ cwÆ ev Svj‡ii cÖ¯’, xw = w D

    2d

    = 1.74 107 1

    2 0.3 103

    = 290 106 m

    cwÆ ev Svj‡ii cÖ‡¯’i ciweZ©b,

    x = xa xw

    = (386.67 106 290 106)m

    = 96.67 106 m

    AZGe, DÏxc‡Ki e¨e ’̄vwU cvwbi g‡a¨ _vK‡j cwÆ ev Svj‡ii cȪ ’

    96.67 106m n«vm cv‡e|

    5bs cÖ‡kœi DËi

    K h‡_vchy³ D”P K¤úv¼wewkó Av‡jvKiwk¥ †Kv‡bv avZec„‡ô AvcwZZ n‡j Zv †_‡K B‡jKUªb wbtm„Z nq, G NUbv‡K Av‡jvK

    Zwor wµqv e‡j|

    L †Kvb †ZRw¯µq c`v‡_©i fvO‡bi nvi wbf©i K‡i bgybvq Dcw¯’Z †gvU cigvYy msL¨vi Dci| ZvB mg‡qi mv‡_ GB nvi Kg‡Z _v‡K|

    fvO‡bi d‡j †ZRw¯µq cigvYyi msL¨v hLb LyeB Kg n‡q hvq,

    ZLb GB nviI bMb¨ n‡q hvq| †h‡nZz cigvYyi msL¨v GKwU c~Y©

    msL¨v, ZvB fvO‡bi nvi Lye bMb¨ n‡j g~jZ Zv `xN© mgq e¨vcx

    cigvYywUi w ’̄wZkxjZv wb‡`©k K‡i| ZvB GB fvOb KL‡bv †kl nq

    bv|

    g‡b Kwi, †Kv‡bv †ZRw¯µq c`v‡_©i bgybvq Avw` ev cÖviw¤¢K

    cigvYyi msL¨v No Ges Aeÿq aªæeK | t mg‡q Aewkó cigvYyi msL¨v, N = Noet

    N = 0 n‡Z n‡j, Noet = 0

    ev, et = 0

    ev, 1

    et = 0

    ev, et = 10

    ev, et =

    ev, t =

    t =

    AZGe, †Kv‡bv †ZRw¯µq c`v‡_©i wbt‡kl Kvj Amxg|

    M DÏxcK n‡Z cvB,

    Y cv‡Zi Kvh©v‡cÿK, Wo = 1.85eV = 1.85 1.6 1019J

    Av‡jvi ª̀æwZ, c = 3 108 ms1

    cø̈ v‡¼i aªæeK, h = 6.63 1034 J.s

    m~PK Zi½‰`N©¨, o = ?

    Avgiv Rvwb, Wo = hc

    o

    ev, o = hcWo

    = 6.63 1034 3 108

    1.85 1.6 1019

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    = 6.72 107m (Ans.)

    N †`Iqv Av‡Q,

    Y cv‡Zi Kvh©v‡cÿK, Wo = 1.85eV

    †Kv‡li ZworPvjK ej, E = 4.2V

    Y †_‡K X G 1 wU B‡jKUªb‡K wb‡q †h‡Z K…ZKvR, W = eE

    = 4.2 eV

    †dvU‡bi m‡e©v”P Zi½‰`N©¨ max n‡j, hc

    max = e (W0 + W)

    ev, max = hc

    e(W0 + W)

    ev, max = 6.63 10–34 3 108

    1.6 10–19 (1.85 + 4.2)

    max = 2054.75Å; hv ̀ „k¨gvb Av‡jvi Zi½‰`‡N©¨i (4000Å – 8000Å) Gi Zzjbvq A‡bK Kg|

    A_©vr „̀k¨gvb Av‡jvi mvnv‡h¨ B‡jKUªb‡K Y cvZ †_‡K X cv‡Z Avbv m¤¢e bq|

    6 bs cÖ‡kœi DËi

    K †Kv‡bv ’̄vqx wbDwK¬qv‡mi fi Gi MVbKvix Dcv`vbmg~‡ni gy³ve ’̄vq f‡ii †hvMd‡ji †P‡q wKQyUv Kg n‡Z †`Lv hvq| f‡ii

    H cv_©K¨‡K fiÎæwU e‡j|

    L cig k~b¨ ZvcgvÎvq Aa©-cwievnxi mn‡hvRx eÜb¸‡jv LyeB mej nq Ges me¸‡jv †hvRb B‡jKUªbB mn‡hvRx eÜb ˆZwi‡Z

    e¨¯Í _v‡K, d‡j †Kv‡bv gy³ B‡jKUªb _v‡K bv| Aa©-cwievnx‡Z Zvc

    w`‡j Zvckw³i Kvi‡Y wKQy msL¨K mn‡hvRx eÜb †f‡½ hvq Ges

    wKQy B‡jKUªb gy³ nq| GB ch©v‡q wefe cv_©K¨ cÖ‡qvM Kiv n‡j

    gy³ B‡jKUªb¸‡jv Zwor cÖevn m„wó K‡i| G Kvi‡Y Aa©-cwievnx‡K

    Zvc w`‡j cwievnxi b¨vq AvPiY K‡i|

    M DÏxcK n‡Z cvB,

    †em cÖev‡ni cwieZ©b, Ib = (22 8)mA = 14 mA

    GwgUvi cÖev‡ni cwieZ©b, Ie = 16 mA

    awi, Kv‡j±i cÖev‡ni cwieZ©b = Ic

    cÖevn weea©b ¸YK, = ?

    Avgiv Rvwb, Ie = Ib + Ic

    ev, Ic = Ie Ib

    = (16 14) mA

    = 2 mA

    Avevi, = IcIe

    = 2

    16

    = 0.125 (Ans.)

    N DÏxc‡Ki UªvbwR÷viwUi weea©b e„w× Ki‡Z n‡j Gi AšÍM©vgx eZ©bx‡K me©`v m¤§yLx eZ©bx‡Z evqvm Kiv nq Ges Zv Kivi Rb¨

    AšÍM©vgx eZ©bx‡Z AšÍM©vgx ms‡K‡Zi AwZwi³ GKwU wW.wm †fv‡ëR

    cÖ‡qvM Ki‡Z nq hv‡K evqvm †fv‡ëR e‡j| m¤§yLx †SuvK †`Iqvq

    AšÍM©vgx eZ©bx‡Z †iva Lye Kg nq| wbtmviK msMÖvnK eZ©bx A_©vr

    ewnM©vgx eZ©bx‡Z Vcc e¨vUvwii gva¨‡g wegyLx †SuvK cÖ`vb Kiv nq|

    wbtmviK cxV Rsk‡b cÖhy³ ms‡K‡Zi abvZ¥K Aa©P‡µi mgq

    Rvsk‡bi m¤§yL †SuvK e„w× cvq d‡j AwaK cwigvY B‡jKUªb

    wbtmviK †_‡K cxV Gi ga¨ w`‡q msMÖvn‡K cÖevwnZ nq Ges

    msMÖvnK cÖevn e„w× cvq| GB †e‡o hvIqv msMÖvnK cÖevn (Ic) †jvW †iwR÷¨vÝ RL-G AwaK cwigvY wefe cZb m„wó K‡i| A_©vr ewnM©vgx‡Z AwaK †fv‡ëR cvIqv hvq|

    3. w`bvRcyi †evW©-2016

    1 bs cÖ‡kœi DËi

    K `ywU wbw`©ó we›`y PvR© GKB wbw`©ó `~i‡Z¡ _vK‡j k~b¨ ev evqy gva¨‡g Zv‡`i g‡a¨ wµqvkxj ej Ges GKB ~̀i‡Z¡ Ab¨ †Kv‡bv

    gva¨‡g Zv‡`i g‡a¨ wµqvkxj e‡ji AbycvZ‡K civ‰e ỳ¨wZK aªæeK

    e‡j|

    L Zwor †ÿ‡Îi †Kv‡bv we›`yi wefe 15 V ej‡Z eySvq, Amxg †_‡K cÖwZ Kzj¤^ abvZ¥K Avavb‡K Zwor‡ÿ‡Îi H we› ỳ‡Z Avb‡Z

    15 J KvR m¤úbœ nq|

    M GLv‡b,

    C1 = 1 F

    C2 = 2 F

    C3 = 3 F

    DÏxc‡Ki wP‡Î, C1 Ges C2 aviKØq mgvšÍiv‡j _vKvq G‡`i Zzj¨aviKZ¡ Cp n‡j,

    Cp = C1 + C2

    = 1 F + 2 F = 3 F

    IB

    Aš—M©vgx

    ms‡KZ

    RL

    VBB VCC

    n-p-n

    + –

    ewnM©v

    B

    C

    +

    Ri E

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    Avevi,

    C2 aviK, Cp Gi mv‡_ †kÖYx‡Z _vKvq G‡`i Zzj¨ aviKZ¡ Cs n‡j,

    1Cs =

    1C3

    + 1CP

    = 1

    3 F +

    1

    3 F =

    2

    3 F

    Cs = 1.5 F

    eZ©bxwUi Zzj¨ aviKZ¡ 1.5F (Ans.)

    N GLv‡b,

    cÖ̀ Ë eZ©bxi Zzj¨ aviKZ¡, C = 1.5uF

    = 1.5 10–6 F

    eZ©bxi wefe, V = 10 V

    cÖ̀ Ë eZ©bxi mwÂZ kw³, U = 12 CV

    2

    = 12 1.5 10

    –6 F (10 V)2

    = 7.5 10–5 J

    Avevi, C1, C2 Ges C3 aviK¸‡jv‡K mgvšÍiv‡j ms‡hvM Ki‡j G‡`i Zzj¨ aviKZ¡ C n‡j,

    C = C1 + C2 + C3

    = 1 F + 2 F + 3 F

    = 6 F

    = 6 10–6 F

    aviK¸‡jv‡K mgvšÍiv‡j hy³ Ki‡j eZ©bxi mwÂZ kw³,

    U = 12 CV

    2

    = 12 6 10

    –6 F (10 V)2

    = 3 10–4 J

    †h‡nZz, U > U

    AZGe, eZ©bxwUi mKj aviK‡K mgvšÍiv‡j ms‡hvM Ki‡j cÖvß

    mwÂZ kw³, cÖ`Ë eZ©bxi mwÂZ kw³ A‡cÿv †ewk n‡e|

    2 bs cÖ‡kœi DËi

    K †Kv‡bv eZ©bx‡Z Zwor cÖevn hw` GKwU wbw`©ó mgq cici w`K cwieZ©b K‡i Ges wbw`©ó mgq cici m‡e©v”P I me©wb¤œ gvb cÖvß

    nq †mB Zwor cÖevn‡K w`K cwieZx© cÖevn e‡j|

    L †Kv‡bv Zvi KzÐjxi ̄ ^Kxq Av‡ek ̧ YvsK 10 †nbix ej‡Z eySvq, H KzÐjx‡Z ZworcÖevn cÖwZ †m‡K‡Û GK A¨vw¤úqvi nv‡i cwieZx©Z

    n‡j, KzÐjxwU‡Z cÖevn cwieZ©‡bi wecix‡Z 10 †fvë Zwo”PvjK kw³ Avweó nq|

    M GLv‡b,

    w`K cwieZx© cÖev‡ni mgxKiY, i = 40 sin t

    kxl©gvb, i = 40 A

    w`K cwieZx© cÖev‡ni eM©g~jxq Mo gvb, irms = ?

    Avgiv Rvwb,

    irms = io

    2

    = 40A

    2

    = 28.28 A (Ans.)

    N GLv‡b,

    w`K cwieZx© cÖev‡ni mgxKiY, i = 40 sin t

    kxl©gvb, i = 40 A

    hLb, t = 3T4 ZLb, i = 40 sin

    3T4

    = 40 sin

    2

    T 3T4

    = 40 sin

    3

    2

    = 40 (–1) = – 40 A = –io

    AZGe, MvwYwZK we‡køl‡Y †`Lv hvq, DÏxc‡K hLb t = 3T4 ZLb

    w`K cwieZx© cÖev‡ni gvb Gi kxl©gv‡bi mgvb|

    3 bs cÖ‡kœi DËi

    K mv`v Av‡jvK iwk¥ wcÖR‡gi ga¨ w`‡q cÖwZmi‡Yi d‡j mvZwU g~j e‡Y©i Av‡jv‡Z wef³ nIqv‡K Av‡jv‡Ki we”QziY e‡j|

    L Kv‡Pi mgeZ©b †KvY 57 ej‡Z eySvq, AmgewZ©Z Av‡jvK iwk¥ Kv‡P 57 †Kv‡Y AvcwZZ n‡j cÖwZdwjZ iwk¥ me©vwaK cwigvY mgeZx©Z n‡e|

    M GLv‡b, DËj †j‡Ýi cÖ_g c„‡ôi eµZvi e¨vmva©, r1 = 6 cm

    wØZxq c„‡ôi eµZvi e¨vmva©, r2 = –12 cm

    †j‡Ýi cÖwZmivsK, = 32

    †j‡Ýi †dvKvm ~̀iZ¡, f = ?

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    Avgiv Rvwb,

    1f = ( – 1)

    1

    r1 –

    1r2

    =

    3

    2 – 1

    1

    6 cm – 1

    –12 cm = 12

    1

    6 – 1

    –12 cm–1

    = 18 cm

    –1

    f = 8 cm

    AZGe, DÏxc‡Ki †jÝwUi †dvKvm ~̀iZ¡ 6 cm| (Ans.)

    N GLv‡b, evqy‡Z †j‡Ýi cÖwZmiv¼, ag = 32

    Ges †dvKvm ~̀iZ¡, a = 8 cm [ÔMÕ bs n‡Z]

    cvwbi cÖwZmivsK, aw = 43

    awi, cvwb‡Z †dvKvm ~̀iZ¡ = w

    †j‡Ýi `yB c„‡ôi eµZvi e¨vmva© r1 I r2 n‡j

    Avgiv Rvwb, 1

    = ( –1)

    1

    r1 –

    1r2

    evZv‡mi †ÿ‡Î, 1

    a = (ag – 1)

    1

    r1 –

    1r2

    ... (i)

    cvwbi †ÿ‡Î, 1

    w = (wg – 1)

    1

    r1 –

    1r2

    ... (ii)

    (i) (ii) bs n‡Z cvB,

    w

    a =

    ag – 1

    wg – 1 =

    ag – 1

    ag

    aw – 1

    =

    32 – 1

    32

    43

    – 1

    =

    12

    18

    = 4

    w = 4 a = (4 8) cm = 32 cm

    AZGe, MvwYwZK we‡køl‡Y †`Lv hvq †h, DÏxc‡Ki †jÝwU‡K hw`

    cvwb‡Z Wzev‡bv nq Z‡e Gi †dvKvm ~̀iZ¡ c~‡e©i †dvKvm ~̀i‡Z¡i 4 ¸Y n‡e Ges †dvKvm ~̀i‡Z¡i gvb n‡e 32 cm|

    4 bs cÖ‡kœi DËi

    K `ªæZMwZ m¤úbœ B‡jKUªb †Kvb avZz‡K AvNvZ Ki‡j Zv †_‡K D”P K¤úvsK I †f`b ÿgZvm¤úbœ ARvbv cÖK…wZi GK cÖKvi

    wewKiY Drcbœ nq, G wewKiY‡K G·-†i e‡j|

    L Avgiv Rvwb 23592 U †K wbDUªb 10n Øviv AvNvZ Ki‡j wbDwK¬q wdkb

    N‡U| G‡Z 23592 U wbDwK¬qvm wefvwRZ n‡q Kg f‡ii ỳwU wbDwK¬qvm

    m„wó nq Ges ỳwU ev wZbwU wbDUªb 10n wbM©Z nq|

    wewµqvq AskMÖnYKvix 10n I

    23592 U Gi †gvU fi A‡cÿv Drcbœ

    wbDwK¬qvmØq I wbDUªb¸wji †gvU fi mvgvb¨ Kg nq| A_©vr wbDwK¬q

    wdk‡b wKQy fi nvivq| AvBb÷vB‡bi fikw³ mgxKiY E = mc2 Abymv‡i GB nviv‡bv fi kw³‡Z iƒcvšÍwiZ nq| BnvB wbDwK¬q

    wdkb wewµqvq kw³ Drc‡bœi KviY|

    M GLv‡b,

    f‚-c„‡ô i‡K‡Ui ˆ`N©̈ , Lo = 10 m

    f‚-c„‡ô w¯’i ch©‡eÿ‡Ki mv‡c‡ÿ i‡K‡Ui †eM, v = 3 107 ms–1

    i‡K‡Ui Pjgvb ˆ`N©¨, L = ?

    Av‡jvi †eM, c = 3 108 ms–1

    Avgiv Rvwb,

    L = Lo 1 – v2

    c2 = 10 1 – (3 107)2

    (3 108)2 = 9.9498 m

    AZGe, i‡K‡Ui Pjgvb ˆ`N©¨ n‡e 9.9498 m (An.s)

    N GLv‡b, f‚-c„‡ô i‡K‡Ui fi, mo = 5000 Kg

    cÖ_g †ÿ‡Î, i‡K‡Ui †eM, v1 = 3 107 ms–1

    wØZxq †ÿ‡Î, i‡K‡Ui †eM, v2 = 2v1 = 2 3 107 ms–1

    = 6 107 ms–1

    Av‡jvi †eM, c = 3 108 ms–1

    cÖ_g †ÿ‡Î i‡K‡Ui Pjgvb fi m1 n‡j

    Avgiv Rvwb,

    m1 = mo

    1 – v12

    c2

    = 5000 kg

    1 – (3 107ms–1)2

    (3 108ms–1)2

    = 5025.189 kg

    Avevi, wØZxq †ÿ‡Î i‡K‡Ui Pjgvb fi m2 n‡j,

    m2 = mo

    1 – v22

    c2

    = 5000 kg

    1 – (6 107ms–1)2

    (3 108ms–1)2

    = 6250 kg

    †h‡nZz, m2 > m1

    AZGe, DÏxc‡K i‡K‡Ui †eM wظY Kiv n‡j Gi fi †e‡o hv‡e|

    5 bs cÖ‡kœi DËi

    K wbDwK¬qvm MVbKvix Dcv`vbmg~‡ni f‡ii mgwó A‡cÿv wbDwK¬qv‡mi fi wKQyUv Kg nq| f‡ii G cv_©K¨‡K fiÎæwU e‡j|

    L iv`vi‡dv‡W©i g‡Z cigvYyi †K‡›`ª i‡q‡Q wbDwK¬qvm †hLv‡b mg¯Í abvZ¥K Avavb Ges fi †K›`ªxf‚Z _v‡K| GB wbDwK¬qv‡mi

    Pviw`‡KB wewÿß Ae ’̄vq i‡q‡Q B‡jKUªb mg~n| A_v©r cigvYyi

    Af¨šÍixY AwaKvsk AÂjB duvKv| ZvB abvZ¥K Avavb hy³

    AwaKvsk -KYv ¯̂Y©cv‡Zi ga¨ w`‡q hvIqvi mgq cÖvq k~b¨

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    RvqMvi ga¨ w`‡q †mvRv c‡_ †ei n‡q hvq| †h me -KYv wbDwK¬qv‡mi cÖvq KvQvKvwQ Avm‡e Zviv wbDwK¬qv‡mi abvZ¥K Avavb

    Øviv weKwl©Z n‡q nvjKv †eu‡K hv‡e| Avi †h me -KYv wbDwK¬qv‡mi w`‡K gy‡LvgywL n‡e Zviv weKwl©Z n‡q wd‡i Avm‡e|

    M GLv‡b, †iwWqv‡gi,

    cÖv_wgK cigvYyi msL¨v, No = 6.023 1023wU

    †f‡½ hvIqv cigvYyi msL¨v = 6.000 1023wU

    Aewkó cigvYyi msL¨v, N = (6.023 – 6.000) 1023wU

    = 2.3 1021wU

    mgq, t = 1y

    †iwWqv‡gi Aeÿq aªæeK n‡j Avgiv Rvwb,

    NNo

    = e–t

    ev, n

    N

    No = –t

    ev, =

    n

    N

    No

    –t

    =

    n

    2.3 10

    21

    6.023 1023

    –1 y

    = 5.568 y–1

    Avevi, Avgiv Rvwb,

    Aa©vqy, T12

    = 0.693

    =

    0.6935.568 y–1 = 0.124 y

    AZGe, †iwWqvg †gŠjwUi Aa©vqy 0.124 eQi (Ans.)

    N wØZxq eQ‡ii ïiæ‡Z AÿZ cigvYy msL¨v,

    No = 2.3 1021wU

    G mgq †_‡K 1 eQi ci cigvYy msL¨v N n‡j,

    N = No e–t

    = 2.3 10–21 e–5.568 y–1 1 y

    = 8.78 1018

    GLv‡b,

    = 5.56 y–1

    myZivs wØZxq eQ‡i †f‡½ hvIqv cigvYy msL¨v,

    No – N = 2.3 1021 – 8.78 1018 = 2.29 1021

    GLv‡b, cÖ_g GK eQi n‡Z cieZ©x GK eQ‡i †f‡½ hvIqv cigvYyi

    msL¨v Kg|

    AZGe, cieZ©x GK eQ‡i †f‡½ hvIqv cigvYyi msL¨v c~e©eZ©x

    GKeQ‡i †f‡½ hvIqv cigvYyi msL¨vi †ewk n‡e bv|

    6 bs cÖ‡kœi DËi

    K Zwor cwievwnZv e„w×i D‡Ï‡k¨ PZz‡h©vRx Aa©cwievnxi g‡a¨ cćhvRx ev w·hvRx c`v‡_©i cigvYy wgwk‡q Gi cwievwnZv e„w×i

    cÖwµqv‡K †Wvwcs e‡j|

    L GKwU P-UvBc I GKwU N-UvBc Aa©-cwievnx‡K we‡kl e¨e ’̄vax‡b mshy³ Ki‡j ms‡hvM c„ô‡K P-N Rvskb e‡j| P-N Rvsk‡bi †h cv‡k P-UvBc AÂj †mLv‡b msL¨v¸iæ evnK †nvj Ges †h cv‡k N-UvBc AÂj †mLv‡b B‡jKUª‡bi AvwaK¨ A‡bK †ewk| hLb P-UvBc AÂj Ges P-UvBc AÂj hy³ nq ZLb N-A‡ji B‡jKUªb¸‡jv P-A‡ji †nvj Øviv AvK…ó n‡q e¨vcb wµqvi gva¨‡g Rvsk‡bi w`‡K Qy‡U hvq| GKBfv‡e P-A‡ji †nvj¸‡jv N-A‡ji B‡jKUªb Øviv AvK…ó n‡q e¨vc‡bi gva¨‡g ms‡hvM ’̄‡ji

    w`‡K Qy‡U hvq| P-N Rvskb ’̄‡j B‡jKUªb I †nvj cigvYy wgwjZ n‡q wbi‡cÿ n‡q hvq| G Kvi‡Y P-N Rvskb Wv‡qv‡Wi wW‡cøkb †jqvi mvgwMÖKfv‡e Zwor wbi‡cÿ|

    M GLv‡b,

    IE = 0.80 mA

    Ges IB = 0.05 mA

    cÖevn jvf, = ?

    Avgiv Rvwb,

    = ICIB

    wKš‘, IE = IC + IB

    IC = IE – IB

    = IE – IB

    IB

    = 0.80 mA – 0.05 mA

    0.05 mA

    = 15

    AZGe, DÏxc‡Ki UªvbwR÷iwUi cÖevn jvf 15| (Ans.)

    N GwU GKwU PNP UªvbwR÷i mvaviY cxV weea©K eZ©bx (eZ©bx‡Z cÖ‡qvRbxq ms‡kvab K‡i †`qv n‡jv)|

    RL

    IE = 0.80 mA; IB = 0.05 mA

    G‡Z wbtmiK I cxV BbcyU Ges cxV I msMÖvnK AvDUcyU wn‡m‡e

    KvR K‡i| wbtmiK Wv‡qvW‡K m¤§yLx evqvm Kivi Rb¨ wbtmiK I

    cx‡Vi g‡a¨ evqvm wefe Vee Ges msMÖvnK Wv‡qvW‡K wegyLx evqvm Kivi Rb¨ msMÖvnK I wbtmi‡Ki g‡a¨ evqvm wefe Vcc cÖ‡qvM Kiv nq| BbcyU evqvm wefe Vbb BbcyU ms‡K‡Zi we Í̄vi wefe †_‡K eo n‡Z n‡e †hb BbcyU ms‡KZ evqvm wef‡ei wecix‡Z wµqv Ki‡jI

    Zv m¤§yLx evqvm wewkó nq| BbcyU eZ©bx‡Z †kÖwY mgev‡q hy³ Ri

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    †iv‡a BbcyU ms‡KZ cÖ‡qvM Kiv nq Ges AvDUcyU eZ©bx‡Z †kÖwY

    mgev‡q hy³ D”P fvi †iva RL †_‡K AvDUcyU ms‡KZ MÖnY Kiv nq|

    BbcyU ms‡KZ wefe VS Gi cwieZ©‡b wbtmiK I cx‡Vi g‡a¨ wefe Vbe cwieZ©xZ nq, d‡j ie-I cwiewZ©Z nq| Vbe e„w× †c‡j cxV msMÖvnK †iva n«vm cvq d‡j msMÖvnK cÖevn ic e„w× cvq| G‡Z cxV msMÖvnK wefe n«vm cvq Ges fvi †iva RL Gi ỳB cÖv‡šÍi wefe ev AvDUcyU wefe VR e„w× cvq| GKBfv‡e Vbe n«vm †c‡j wbtmiK

    msMÖvnK †iva e„w× cvq d‡j msMÖvnK cÖevn ic n«vm cvq| G‡Z wbtmiK msMÖvnK wefe e„w× cvq Ges fvi †iva RL Gi ỳB cÖv‡šÍi wefe ev AvDUcyU wefe VR n«vm cvq| RL Gi †iva Lye †ewk nIqvq ic Gi mvgvb¨ cwieZ©‡b VR Gi cwieZ©b Lye †ewk nq| myZivs, ejv hvq, VS Gi mvgvb¨ cwieZ©‡b VR Gi cwieZ©b Lye †ewk nq| ZvB Bbcy‡U GKwU Kg we¯Ív‡ii ms‡KZ cÖ‡qvM Kiv n‡j AvDUcy‡U GKwU

    †ewk we¯Ív‡ii ms‡KZ cvIqv hvq A_©vr ms‡KZwU weewa©Z nq|

    4. Kzwgjøv †evW©-2016

    1 bs cÖ‡kœi DËi

    K †h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b Ki‡Z cv‡i Ges m¤§yLeZ©x I wecixZgyLx cÖwµqvi cÖwZ¯Í‡i Zvc I Kv‡Ri djvdj

    mgvb I wecixZ nq, †mB cÖwµqv‡K cÖZ¨veZ©x cÖwµqv e‡j|

    L Zvc BwÄb D”P ZvcgvÎvi Drm n‡Z Zvc MÖnY K‡i Kvh© m¤úv`b K‡i Ges Ae¨en„Z Zvc wb¤œ ZvcgvÎvi ZvcMÖvn‡K ewR©Z

    K‡i|

    †iwd«‡R‡iUi wb¤œ ZvcgvÎvi Drm †_‡K Zvc MÖnY ev AcmviY K‡i

    I D”P ZvcgvÎvi Avav‡i eR©b K‡i| Gi Rb¨ evB‡i †_‡K kw³

    mieivn Ki‡Z nq|

    M GLv‡b BwÄb KZ…©K M„wnZ Zvc, Q1 = 1260J BwÄb KZ…©K ewR©Z Zvc, Q2 = 930J

    Avgiv Rvwb, Bwćbi `ÿZv,

    = 1 Q2Q1

    = 1 930

    1260 = 0.262

    = 26.2%

    AZGe Bwćbi `ÿZv = 26.2% (Ans.)

    N ÔMÕ n‡Z BwÄbwUi `ÿZv, = 26.2%

    BwÄbwU cÖZ¨vMvgx n‡j Gi `ÿZv n‡e,

    = 1 T2T1

    = 1 310420

    = 0.262

    = 26.2%

    GLv‡b,

    Dr‡mi ZvcgvÎv, T1 = 147C

    = 420K

    MÖvn‡Ki ZvcgvÎv, T2 = 37C

    = 310K

    =

    †h‡nZz BwÄbwUi `ÿZv cÖZ¨vMvgx Bwćbi `ÿZvi mgvb ZvB

    BwÄbwU cÖZ¨vMvgx|

    2 bs cÖ‡kœi DËi

    K Zwor w؇giæi †h †Kvb GKwU Pv‡R©i gvb Ges G‡`i ga¨eZ©x `~i‡Z¡i ¸Ydj‡K wØ-†giæ åvgK e‡j|

    L avi‡K kw³ mÂq Ki‡Z n‡j avi‡K wKQy PvR© Rgv Ki‡Z n‡e| G PvR© avi‡K GKev‡i †`qv m¤¢e bq| GKUz GKUz K‡i PvR© Rgv

    Ki‡Z nq| KviY GwU wKQy PvR© jvf Kivi ci cieZ©x PvR© cÖ`v‡b

    evav †`q| ZvB †Kv‡bv aviK‡K PvwR©Z Ki‡Z wKQy KvR Ki‡Z nq

    ev wKQy kw³ e¨q nq| G e¨wqZ kw³ avi‡K Zwor kw³ wn‡m‡e Rgv

    _v‡K|

    M

    5 4

    E = 24 Volt

    r = 2

    5 4

    I

    GLv‡b, Zwo”PvjK ej, E = 24V

    Af¨šÍixY †iva, r = 2

    GLv‡b, 4 Ges 5 †kÖwY mgev‡q _vKvq Zv‡`i Zzj¨‡iva, R1 = 4 + 5 = 9

    Avevi, 5 Ges 4 †iva †kÖwY mgev‡q _vKvq Zv‡`i Zzj¨‡iva, R2 = 5 + 4 = 9

    R1 Ges R2 ci¯úi mgvšÍiv‡j mshy³ _vKvq eZ©bxi Zzj¨‡iva R n‡j,

    1R

    = 1R1

    + 1R2

    = 1

    9 +

    1

    9 =

    1 + 1

    9 =

    2

    9

    R = 92

    = 4.5

    Avgiv Rvwb, Zwor cÖevn, I = E

    R + r =

    24V

    4.5 + 2

    ev, I = 3.69A

    AZGe, eZ©bxi Zwor cÖevn, I = 3.69A (Ans.)

    N

    R1 = 4

    i2

    i4 R4 = 4

    i1 R2 = 5

    i3 G

    ig

    A B P

    Q C D

    R3 = 5

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    P I Q we›`y‡Z wKik‡di cÖ_g m~Îvbymv‡i,

    i1 = i3 + ig

    i2 = i4 ig

    Avevi, APQDA I PBCQP jy‡c wØZxq m~Î cÖ‡qvM K‡i cvB,

    R1i1 + igG R3i2 = 0

    R2i3 R4i4 igG = 0

    ev, 4i1 + igG 5i2 = 0

    5i3 4i4 igG = 0

    4i1 + 5i3 5i2 4i4 = 0

    4i3 + 4ig + 5i3 5i4 + 5ig 4i4 = 0

    9i3 + 9ig 9i4 = 0

    ig = i4 i3

    †h‡nZz R4 R2

    †m‡nZz i4 i3

    myZivs ig abvZ¥K

    A_©vr ig Gi w`K P †_‡K Q Gi w`‡K|

    3 bs cÖ‡kœi DËi

    K †Kvb ’̄v‡b GKB mg‡q GKwU Zwor‡ÿÎ I GKwU †PŠ¤̂K‡ÿÎ we`¨gvb _vK‡j †mLv‡b GKwU MwZkxj Avavb †h jwä ej Abyfe

    K‡i Zv‡K j‡iÄ ej e‡j|

    L †Kvb KzÐjxi ¯̂Kxq Av‡ek ¸YvsK 8H ej‡Z eySvq, †mB KzÐjx‡Z cÖwZ †m‡K‡Û Zwor cÖevn 1A nv‡i cwiewZ©Z n‡j D³

    KzÐjx‡Z cÖevn cwieZ©‡bi wecix‡Z 8V Zwor PvjK kw³ Avweó nq|

    M GLv‡b, A Zv‡i Zwor cÖevn, i1 = 12A

    B Zv‡i Zwor cÖevn, i2 = 15A

    Zvi؇qi ga¨eZ©x ~̀iZ¡, r = 5 cm = 0.05m

    A Zv‡ii cÖwZ GKK ˆ`‡N©¨ †PŠ¤̂K e‡ji gvb, Fl = ?

    Avgiv Rvwb,

    Fl = 0i1i22r

    = 4 107Wb/Am 12A 15A

    2 0.05

    = 7.2 104 N/m

    AZGe, A-Zv‡ii cÖwZ GKK ˆ`‡N©¨ †PŠ¤̂K e‡ji gvb 7.2 104 N/m (Ans.)

    N GLv‡b, A-Zv‡i Zwor cÖevn, i1 = 12A

    B-Zv‡i Zwor cÖevn, i2 = 15A

    Zvi؇qi ga¨eZ©x ~̀iZ¡, r = 5cm = 0.05m

    A Zvi n‡Z P we›`yi ~̀iZ¡ = B Zvi n‡Z P we›`yi ~̀iZ¡, d = 0.025 m

    A Zv‡ii Rb¨ P we›`yi †PŠ¤̂K‡ÿ‡Îi cÖvej¨,

    B1 = 0i12d

    = 4 107Wb/mA 12A

    2 0.025

    = 9.6 105 Wb/m2

    †d¬wgs Gi Wvbn Í̄ wbqgvbyhvqx, B1 Gi w`K KvMR Z‡ji j¤̂ eivei †fZ‡ii w`‡K|

    Avevi,

    B Zv‡ii Rb¨ P we› ỳ‡Z †PŠ¤^K‡ÿ‡Îi cÖvej¨,

    B2 = 0i12d

    = 4 107Wb/Am 15A

    2 0.025 m

    = 1.2 104 Wb/m2

    †d¬wgs Gi Wvbn Í̄ wbqgvbyhvqx B2 Gi w`K KvMR Z‡ji j¤^ eivei evB‡ii w`‡K A_ev B1 Gi wecixZ w`‡K|

    myZivs, P we› ỳ‡Z jwä †PŠ¤^K cÖvej¨, B = B2 B1

    = 1.2 104 Wb/m2 9.6 105 Wb/m2

    = 2.4 105 Wb/m2

    B Gi w`K n‡e KvMR Z‡ji mv‡_ j¤^ eivei evB‡ii w`‡K|

    Avevi, B Zv‡ii cÖevn wecixZgyyLx Ki‡j †d¬wgs Gi Wvbn Í̄ wbqgvbyhvqx B2 †PŠ¤̂K‡ÿ‡Îi w`K cwiewZ©Z n‡e Ges Zvi w`K n‡e KvMR Z‡ji j¤̂ eivei †fZ‡ii w`K A_©vr B1 Gi w`‡Ki Abyiƒc|

    AZGe, P we›`y‡Z jwä cÖvej¨, B = B1 + B2

    = 1.2 104 Wb/m2 + 9.6 10–5 Wb/m2

    = 2.16 104 Wb/m2 2.4 10–5 Wb/m2

    B Gi w`K n‡e KvMR Z‡ji mv‡_ j¤^ eivei wfZ‡ii w`‡K

    myZivs, P we› ỳ‡Z †PŠ¤^K‡ÿ‡Îi gvb I w`K DfqB cwiewZ©Z n‡e|

    4 bs cÖ‡kœi DËi

    K Av‡jvi iwk¥ GK we›`y †_‡K Ab¨ we›`y‡Z hvevi mgq m¤¢ve¨ mKj c‡_i g‡a¨ †mB c_ AYymiY K‡i †h c‡_ mgq me †_‡K Kg

    jv‡M|

    L Avgiv Rvwb, GKwU wbw`©ó e‡Y©i Av‡jvi Rb¨ †Kv‡bv gva¨‡gi cÖwZmiYvsK GKwU aªæe msL¨v| wKš‘ wewfbœ e‡Y©i Av‡jvi Rb¨ GB

    msL¨v wewfbœ| wewfbœ e‡Y©i Av‡jvi cÖwZmiv¼ wewfbœ nIqvq †hŠwMK

    Av‡jv GK gva¨g †_‡K Ab¨ gva¨‡g cÖwZmi‡Yi mgq GKB †Kv‡Y

    AvcwZZ n‡jI wewfbœ e‡Y©i cÖwZmiY †KvY wewfbœ nq| d‡j

    eY©̧ ‡jv ci¯úi †_‡K Avjv`v n‡q c‡o| wcÖR‡g Av‡jv cÖwZmi‡Yi

    †ÿ‡Î ỳB evi f‚wgi w`‡K †eu‡K hvq| ZvB wewfbœ Av‡jvK iwk¥i

    Rb¨ AvcZb †KvY GK n‡jI wbM©gb †KvY i2 wfbœ nq| Avgiv Rvwb wcÖR‡gi wePz¨wZ, = (i1 + i2) A| i2 wfbœ nIqvi Kvi‡Y wewfbœ e‡Y©i wePz¨wZ wfbœ nq| G Kvi‡Y mv`v Av‡jv wcÖR‡gi ga¨ w`‡q cÖwZmi‡Yi

    mgq we”QzwiZ nq|

    M †`Iqv Av‡Q,

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    Zi½‰`N©¨, = 3800 A = 3800 10–10m

    S, S2 = wPo؇qi ~̀iZ¡ = d = 0.5mm = 0.5 10–3 m

    D = wPo n‡Z c ©̀vi ~̀iZ¡ = 1m, n = 5

    cÂg AÜKvi †Wvivi ~̀iZ¡, xn = ?

    Avgiv Rvwb, n Zg AÜKvi †Wvivi ~̀iZ¡, xn = (2n 1) D2d

    = (2 5 1) 3800 1010m 1m

    2 0.5 103m

    = 3.42 103m

    AZGe, 5g AÜKvi †Wvivi ~̀iZ¡ = 3.42 103 m

    = 3.42 mm

    N Avgiv Rvwb,

    = S2P S1P = xdD

    = 6.46 103m 0.5 103m

    1m

    = 3.23 106m

    GLv‡b,

    x = 6.46 103m

    d = 0.5 103m

    D = 1m

    = 3800 1010m

    e¨vwZPv‡ii kZ© †_‡K Rvwb,

    g‡b Kwi,

    c_ cv_©K¨ =

    = n

    n = S2P S1P

    = 3.23 106m

    3800 1610m

    = 172

    = 17 12

    n c~Y© msL¨v n‡j MVb g~jK Avi A‡a©‡Ki †e‡Rvo ¸wYZK n‡j aŸsmvZ¥K e¨vwZPvi n‡e|

    GLv‡b, n, 12

    Gi †e‡Rvo ¸wYZK

    myZivs P we› ỳ‡Z aŸsmvZ¥K e¨vwZPvi m„wó n‡e|

    5 bs cÖ‡kœi DËi

    K mvaviY cxV web¨v‡mi †ÿ‡Î †Kv‡bv UªvbwR÷‡ii wbtmiK

    cÖev‡ni cwieZ©‡bi mv‡c‡ÿ msMÖvnK cÖev‡ni cwieZ©‡bi nvi icie

    †K cÖevn weea©b ¸YK e‡j|

    L Aa© cwievnx‡Z †hvRb e¨vÛ c~Y© Ges cwienb e¨v‡Û †Kv‡bv B‡j±ªb _v‡K bv, wKš‘ †hvRb e¨vÛ I cwienb e¨v‡Ûi g‡a¨ kw³

    e¨eavb Lye Kg _v‡K| mvaviY ZvcgvÎvq †hvRb e¨v‡Ûi wKQy

    B‡jKUªb †hvRbx eÜb †f‡½ cwienb e¨v‡Û P‡j hvq d‡j Giv

    mvgvb¨ cwievnx nq| ZvcgvÎv e„w×i mv‡_ mv‡_ GKwU wbw`©ó

    ZvcgvÎv ch©šÍ †hvRb e¨v‡Ûi wKQy B‡jKUªb Zvcxq kw³ MÖnY K‡i

    cwienb e¨v‡Û P‡j Av‡m A_©vr cwienb e¨v‡Û B‡jKUªb msL¨v e„w×

    cvq ZvB ZvcgvÎv e„wׇZ Aa© cwievnxi cwievwnZv e„w× cvq Ges

    †iva n«vm cvq|

    M GLv‡b, wbe„wË wefe, V0 = 2V

    B‡jKUª‡bi fi, m = 9.1 1031 kg

    B‡jKUª‡bi m‡e©v”P †eM, vmax = ?

    Avgiv Rvwb, 12

    m vma2

    x = eV0

    ev, vmax2 =

    eV0 2m

    = 1.6 1019C 2v 2

    9.1 1031kg

    ev, vma2

    x = 7.0329 1011 m2/s2

    vmax = 8.386 105 m/s

    AZGe, d‡UvB‡jKUª‡bi m‡e©v”P MwZ‡eM = 8.386 105 m/s (Ans.)

    N GLv‡b,

    AvcwZZ †dvU‡bi Zi½‰`N©¨, = 4 107m

    wbe„wË wefe, V0 = 2V

    cø̈ v‡¼i aªæeK, h = 6.63 1034Js

    Av‡jvi †eM, c = 3 108 m/s

    jvj Av‡jvi Zi½‰`N©¨, R = 6.8 107m

    Avgiv Rvwb,

    AvcwZZ †dvU‡bi kw³, E = hc

    = (6.63 1034Js) 3 108m/s

    4 107m

    = 4.973 1019J

    GLb, Kvh©v‡cÿK, W = E eV0

    = 4.973 1019J (1.6 1019C 2V)

    = 1.773 1019J

    jvj e‡Y©i †dvU‡bi kw³, ER = hc

    = (6.63 1034 Js) 3 108 m/s

    6.8 107m

    = 2.925 1019J

    †h‡nZz, ER W

    myZivs, jvj Av‡jv e¨envi Ki‡j d‡UvZwor cÖevn NU‡e|

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    6 bs cÖ‡kœi DËi

    K Zwor Dr‡mi abvZ¥K I FYvZ¥K cÖvšÍ‡K h_vµ‡g Rvsk‡bi P I n A‡ji mv‡_ hy³ Kiv n‡j Rsk‡bi wefe cÖvPxi n«vm cvq Ges cÖevn mnR nq e‡j G ai‡bi ms‡hvM‡K m¤§yLx †SuvK e‡j|

    L Awbqwš¿Z wbDwK¬qvi wewµqvi cÖwZ P‡µ cigvYyi fvO‡bi mv‡_ mv‡_ wewµqv msNUbKvix wbDUªb gy³ nq Ges cÖwZwU gy³ wbDUª‡bi

    AvNv‡Z cieZx© cigvYywUI fv‡O Ges 3wU K‡i wbDUªb gy³ nq| Gfv‡e cÖwZP‡µ wbDUª‡bi msL¨v e„w× cvq Ges kw³ Drcv`‡bi

    nviI evo‡Z _v‡K| AZGe, ejv hvq †h wdkb GKwU ¯̂ZtùzZ©

    wewµqv| GKevi G wewµqv ïiæ K‡i w`‡j Zv Awbqwš¿Z fv‡e Pj‡Z

    _v‡K Ges cÖPzi kw³ Drcbœ K‡i| ZvB Awbqwš¿Z wbDwK¬qvi

    wewµqvq AwZwi³ kw³i cÖ‡qvRb nq bv|

    M GLv‡b, mvaviY f‚wg n-p-n eZ©bx‡Z,

    BbcyU cÖevn, IE = 25 mA

    AvDUcyU cÖevn, IC = 20 mA

    f‚wg cÖevn, IB = ?

    Avgiv Rvwb, IE = IB + IC

    IB = IE IC

    = 25 mA 20 mA = 5 mA (Ans.)

    N DÏxc‡K ivBmv cÖ_‡g GKwU †÷c-WvDb UªvÝdg©vi e¨envi K‡i 220V Gwm‡K 12V Gwm‡Z bvwg‡q Av‡b| UªvÝdg©viwUi g~L¨ I †MŠY KzÐjxi †fv‡ëR h_vµ‡g EP = 220V I Es = 12V n‡j Ges g~L¨ I †MŠY KzÐjxi cvKmsL¨v h_vµ‡g np I ns n‡j,

    EpEs

    = npns

    ev, 220V12V

    = npns

    12V

    220V

    ev, npns

    = 553

    AZGe, ivBmv cÖ_‡g (55 t 3) Abycv‡Z GKwU †÷cWvDb UªvÝdg©v‡ii mvnv‡h¨ 12V G bvwg‡q G‡b‡Q|

    wØZxq †ÿ‡Î ivBmv GKwU c~Y©Zi½ †iKwUdvqvi e¨envi K‡i 12V Gwm‡K 12V wWwm‡Z cwiewZ©Z Kivq wUwfwU Pj‡Z Avi¤¢ KiwQj| wb‡P c~Y©Zi½ †iKwUdvqvi eZ©bxi wPÎ †`qv n‡jv|

    12 V AC O

    +

    A D1

    P

    B

    RL

    mgq

    D2

    D1 D2 D1 D2

    c~Y©Zi½ †iKwUdvqviwU‡Z Gwm AšÍM©vgx Dr‡mi ỳyB PµB Kv‡R

    jvMv‡bv nq| GRb¨ eZ©bx‡Z `ywU Wv‡qvW D1 I D2 e¨envi Kiv nq| Wv‡qvW ỳwU‡K UªvÝdg©viwUi †MŠYKzÐjxi AB As‡ki mv‡_ ms‡hvM †`Iqv n‡q‡Q| Wv‡qvW D1 Gwm AšÍM©vgx Dr‡mi †MŠbKzÐjxi OA As‡k AvMZ Dc‡ii Aa©Pµ‡K †iKwUdvB K‡i Ges Wv‡qvW D2 †MŠYKzÐjxi OB As‡k AvMZ wb‡Pi Aa©Pµ‡K †iKwUdvB K‡i| Gwm AšÍM©vgxi cÖ_g abvZ¥K Aa©P‡µi Rb¨ A abvZ¥K nq| d‡j Wv‡qvW D1 m¤§~Lx †SuvK cÖvß nIqvq Gi ga¨ w`‡q Zwor cÖevwnZ nq| wKš‘ D2 Wv‡qvW wegyLx †SuvK cÖvß nIqvq Gi ga¨ w`‡q Zwor cÖevwnZ n‡Z cvv‡i bv| G‡ÿ‡Î O A D1 P O c‡_ Zwor cÖevwnZ nq|

    AšÍM©vgxi wØZxq Aa©P‡µi Rb¨ A cÖvšÍ FbvZ¥K Ges B cÖvšÍ abvZ¥K nq| d‡j Wv‡qvW D2 m¤§yLx †SvK cÖvß nIqvq Gi ga¨ w`‡q Zwor cÖevwnZ nq wKš‘ D1 wegyLx †SuvK cÖvß nIqvi Gi g‡a¨ w`‡q †Kv‡bv Zwor cÖevwnZ nq bv| G‡ÿ‡Î O B D2 P O c‡_ Zwor cÖevwnZ nq| eZ©bxi R2 †iv‡ai ’̄v‡b wUwfwU‡K ’̄vcb Ki‡j Dfq †ÿ‡ÎB wUwfi ga¨ w`‡q GKB w`‡K Zwor cÖevwnZ nq A_©vr wUwfwUi ga¨ w`‡q

    GKgyLx Zwor ev wWwm cÖevn cÖevwnZ nq|

    5. PÆMÖvg †evW©-2016

    1 bs cÖ‡kœi DËi

    K †Kvb wm‡÷‡gi AšÍf‚©³ c`v_©mg~‡ni Af¨šÍi ’̄ AYy-cigvYy I †gŠwjK KYvmg~‡ni ̂ iwLK MwZ, ̄ ú›`b MwZ I N~Y©bMwZ Ges Zv‡`i

    g‡a¨Kvi e‡ji Kvi‡Y D™¢‚Z kw³ hv Kvh© m¤úv`b Ki‡Z cv‡i, Ab¨

    kw³‡K iƒcvšÍwiZ n‡Z cv‡i Ges hvi gvb I cÖK…wZ c`v‡_©i Zvcxq

    Ae¯’v, `kv BZ¨vw` wba©viY K‡i, ZvB Af¨šÍixY kw³|

    L cÖK…wZ‡Z mewKQyB mvg¨ve ’̄v †c‡Z †Póv K‡i| GKwU wm‡÷g hZB mvg¨ve ’̄vi w`‡K GwM‡q hvq ZZB Zvi KvQ †_‡K KvR cvIqvi

    m¤¢vebv K‡g hvq, mvg¨ve ’̄vq †cŠQ‡j wm‡÷g †_‡K Avi KvRB

    cvIqv hvq bv| wm‡÷‡gi GB kw³ iƒcvšÍ‡ii AÿgZvB n‡”Q

    G›Uªwc| GK ev GKvwaK wm‡÷g hZ mvg¨ve ’̄vi w`‡K GwM‡q hvq

    Zv‡`i G›UªwcI ZZ evo‡Z _v‡K| mvg¨ve ’̄vq G›Uªwc me‡P‡q †ewk

    nq| †h‡nZz cÖK…wZ‡Z mewKQyB mvg¨ve ’̄v †c‡Z hvq, ZvB ejv hvq

    RM‡Z G›Uªwc µgvMZ evo‡Q| RM‡Z G›Uªwc hLb m‡e©v‡”P †cŠuQv‡e

    ZLb me wKQyi ZvcgvÎv GK n‡q hv‡e| d‡j Zvckw³‡K Avi

    hvwš¿K kw³‡Z iƒcvšÍwiZ Kiv hv‡e bv| GB Ae ’̄v‡K RM‡Zi

    Z_vKw_Z Zvcxq g„Zz¨ bv‡g AwfwnZ Kiv n‡q‡Q|

    M DÏxcK n‡Z cvB

    Dr‡mi ZvcgvÎv, T1 = 900C = 1173K

    MÖvn‡Ki ZvcgvÎv, T2 = 30C = 303K

    `ÿZv, = ?

    Avgiv Rvwb,

    =

    T1 – T2

    T1 100%

    =

    1173 – 303

    1173 100%

    = 74.168% (Ans.)

    N BwÄbwUi Zvcxq `ÿZv,

    =

    1 –

    T2T1

    100%

    = 100% n‡j,

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    1 –

    T2T1

    100% = 100%

    ev, 1 – T2T1

    = 1

    ev, T2T1

    = 0;

    wKš‘ Zv ZLbB m¤¢e hw` T2 = OK A_ev T1 = nq|

    myZivs Zvc Bwćbi Kg©`ÿZv 100% †c‡Z n‡j Dr‡mi ZvcgvÎv Amxg ev wms‡¼i ZvcgvÎv cig k~b¨ n‡Z n‡e|

    2 bs cÖ‡kœi DËi

    K evwn¨K Zwor †ÿ‡Îi cÖfv‡e †h mKj gva¨‡gi cÖwZwU cigvYy GK GKwU Zwor w؇giæ‡Z cwiYZ nq Zv‡K civwe ỳ¨r ev

    WvBB‡jKwUªK e‡j|

    L AwaK cwigvY cÖevn wM‡q hv‡Z M¨vjfv‡bvwgUvi‡K bó Ki‡Z bv cv‡i Zvi Rb¨ M¨vjfv‡bvwgUv‡ii mv‡_ mgvšÍivj mgev‡q GKwU

    Aí gv‡bi †iva kv›U wn‡m‡e mshy³ Kiv nq| Gi d‡j g~j cÖevn

    `yÕfv‡M wef³ n‡q hvq Ges kv‡›Ui †iva Kg nIqvq †ewk cwigvY

    cÖevn Gi †fZi w`‡q cÖevwnZ nq Ges Aí cwigvY cÖevn

    M¨vjfv‡bvwgUv‡ii ga¨ w`‡q cÖevwnZ nq| G‡Z M¨vjfv‡bvwgUvi bó

    nIqvi nvZ †_‡K iÿv cvq|

    M DÏxcK n‡Z cvB;

    aviKZ¡, C1 = C2 = C3 = 180F = 180 10–6F

    wefe cv_©K¨, V = 3V

    Zzj¨ aviKZ¡, Cs = ?

    mwÂZ wefe kw³, U = ?

    Avgiv Rvwb, 1Cs

    = 1C1

    + 1C2

    + 1C3

    ev, 1Cs

    = 1

    180 10–6 +

    1

    180 10–6 +

    1

    180 10–6

    Cs = 6 10–5 F

    Avevi, U = 12 CsV

    2 = 12 6 10

    –5 (3)2

    = 2.7 10–4 J (Ans.)

    N †ikgv †Kvl wZbwU‡K †kÖYx mgev‡q hy³ K‡i Zwo”PvjK kw³

    E = 3 + 3 + 3 = 9 V a‡i wnmve K‡i, Zwor cÖevn I wbY©q K‡i,

    I = ER =

    950 = 0.18 A

    †ikgvi fzj n‡jv, †m Zwor †Kvl¸‡jv‡K mgvšÍiv‡j hy³ bv K‡i

    †kÖYx mgev‡q hy³ K‡i Zwo”PvjK kw³ 9 V a‡iwQj|

    wkÿ‡Ki wb‡ ©̀kbv †gvZv‡eK mwVK eZ©bxwU n‡e wb¤œiƒc :

    Avgiv Rvwb, mgvb Zwo”PvjK e‡ji KZK¸‡jv †Kv‡li mgvšÍivj

    mgev‡q Zwo”PvjK ej GKwU †Kv‡li Zwo”PvjK e‡ji mgvb nq|

    EP = 3V

    R = 50

    IP = EPR =

    350

    = 0.06 A (Ans.)

    3 bs cÖ‡kœi DËi

    K †Kvb cvZ AvK…wZi Zworevnx cwievnx‡K †PŠ¤^K †ÿ‡Îi mv‡_ j¤^fv‡e ̄ ’vcb Kiv n‡j ZworcÖevn I †PŠ¤̂K †ÿÎ Df‡qi mv‡_ j¤̂

    eivei ỳB wecixZ c„‡ô GKwU wefe cv_©K¨ m„wó nIqvi NUbvB nj

    wµqv|

    L 220V D.C Øviv hw` †Kv‡bv e¨w³ ˆe`y¨wZK kK cvb Zvn‡j wZwb m‡e©v”P 220V ØvivB kK cvb| wKš‘ †Kv‡bv e¨w³ hw` 220V A.C Øviv

    kK cvb Z‡e wZwb m‡e©v”P 2 200V = 311V Øviv kK cv‡eb| G Kvi‡Y DC 220V A‡cÿv AC 220V †ewk wec¾bK|

    M DÏxcK n‡Z cvB,

    w`K cwieZx© cÖev‡ni kxl©gvb, Io = 2A

    mgq, t = 7.5 T

    4

    Zwor cÖevn I = ?

    Avgiv Rvwb,

    I = Io sin t

    = 2 sin

    2

    T 7.5 T

    4

    = 2 sin

    180 7.5

    2

    = 2 sin 675

    = – 1.414 A

    Zwor cÖev‡ni gvb, I = 1.414 A (Ans.)

    N DÏxcK n‡Z cvB,

    †MŠY KzÐjxi †iva, Rs = 17.5

    †MŠY KzÐjxi ÿgZv, Ps = 140 W

    R = 50

    3V

    3V

    3V

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    gyL¨ KzÐjxi cÖev‡ni kxl©gvb, Io = 2 A

    Avgiv Rvwb,

    IP = 0.707 Io

    = 0.707 2

    = 1.414 A

    Avevi, PS = I2

    S RS

    ev, IS = PSRS

    = 14017.5 = 2.828 A

    Avevi,

    NPNS

    = ISIP

    ev, NPNS

    = 2.8281.414

    NPNS

    = 2

    AZGe, UªvÝdg©viwUi †MŠY KzÐjx‡Z 140 W ÿgZv †c‡Z n‡j gyL¨

    KzÐjx I †MŠY KzÐjxi cvKmsL¨vi AbycvZ 2 : 1 Ki‡Z n‡e|

    4 bs cÖ‡kœi DËi

    K cvkvcvwk Aew¯’Z ỳwU mymsMZ Drm †_‡K wbM©Z mgvb K¤úv¼ I we Í̄v‡ii ỳwU Av‡jvK Zi‡½i DcwicvZ‡bi d‡j ch©vqµ‡g

    D¾¡j I AÜKvi Ae ’̄vi m„wó nIqv‡K Av‡jvi e¨wZPvi e‡j|

    L Kv‡Pi msKU †KvY 42 ej‡Z eySvq, k~b¨ gva¨g (ev evqy) I Kv‡Pi we‡f`Z‡j KvP †_‡K 42 †Kv‡Y AvcwZZ iwk¥ we‡f`Zj †Nu‡l cÖwZmwiZ n‡e| AvcZb †Kv‡Yi gvb 42 Gi †P‡q †ewk n‡j Av‡jvK iwk¥ cÖwZmwiZ bv n‡q KuvP gva¨‡g c~Y© Af¨šÍixY fv‡e

    cÖwZdwjZ n‡e|

    M DÏxcK n‡Z cvB,

    jÿ¨ e¯‘i ~̀iZ¡, u = 15 cm

    jÿ¨ e¯‘i ˆ`N©¨, = 5 cm

    we‡¤^i ˆ`N©¨, = 10 cm

    Avgiv Rvwb, |M| =

    =

    10 cm5 cm = 2.

    Avevi, |M| = vu

    ev, 2 = vu

    v = 2u

    †h‡nZz we¤^wU Aev Í̄e,

    v = – 2u = –2 15 cm = – 30 cm

    Avgiv Rvwb, 1f =

    1u +

    1v =

    115 –

    130 =

    130

    f = 30 cm = 0.3 m

    Avevi, P = 1f =

    10.3 = 3.33 D (Ans.)

    N †jÝwU‡K mij AYyexÿY hš¿ wn‡m‡e e¨envi K‡i ̄ úó cÖwZwew¤^ cvIqvi Rb¨ Aev Í̄e we¤^wU †Pv‡Li ̄ úó `k©‡bi wbKU we› ỳ‡Z MwVZ

    n‡Z n‡e|

    A_©vr G‡ÿ‡Î, we‡¤̂i ~̀iZ¡, v = – D = – 25 cm

    ÔMÕ Ask n‡Z cvB, †jÝwUi †dvKvm ~̀iZ¡, f = 30 cm

    e¯‘ n‡Z †j‡Ýi ~̀iZ¡ u n‡j,

    1u +

    1v =

    1f

    ev, 1u =

    1f –

    1v =

    130 +

    125 =

    11150

    u = 13.64 cm

    AZGe, †jÝwU‡K mij AbyexÿY hš¿ wn‡m‡e e¨envi K‡i ¯úó

    cÖwZwe¤^ †`L‡Z n‡j e¯‘ †_‡K †jÝwU‡K 13.64 cm ̀ ~‡i ̄ ’vcb Ki‡Z

    n‡e|

    5bs cÖ‡kœi DËi

    K ch©‡eÿ‡Ki mv‡c‡ÿ MwZkxj _vKvi Kvi‡Y †Kv‡bv `‡Ði ˆ`N©¨ msKzwPZ g‡b nIqvi NUbv‡K ˆ`N©¨ ms‡KvPb e‡j|

    L B‡jKUª‡bi Zvcxq wbtmiY I d‡UvZwor wbtmi‡Yi g‡a¨ ỳwU cv_©K¨ wb‡P D‡jøL Kiv n‡jv :

    (i) d‡UvZwor wbtmi‡Yi Rb¨ h‡_vchy³ K¤úvsK wewkó Av‡jvK iwk¥i cÖ‡qvRb| B‡jKUª‡bi Zvcxq wbtmi‡Yi †ÿ‡Î wfbœ avZzi

    `yBwU Zv‡ii ms‡hvM؇q wfbœ ZvcgvÎvi cv_©K¨ _v‡K|

    (ii) d‡UvZwor wbtmiY GKwU ZvrÿwYK NUbv| B‡jKUª‡bi Zvcxq wbtmiY GKwU mgq mv‡cÿ NUbv|

    M DÏxcK n‡Z cvB,

    B †gŠ‡ji Aa©vqy, T12

    = 9 days

    B †gŠ‡ji Mo Avqy, = ?

    Avgiv Rvwb,

    T12

    = 0.693

    ev, =

    T12

    0.693 = 9

    0.693 = 12.987 days (Ans.)

    N GLv‡b,

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    A †gŠ‡ji Aa©vqy, T12

    = 6d

    A †gŠ‡ji Aeÿq aªæeK, A = 0.693

    T12

    = 0.693

    6d = 0.11155d1

    Avevi,

    B †gŠ‡ji Aa©vqy, T12

    = 9d

    B †gŠ‡ji Aeÿq aªæeK, B = 0.693

    T12

    = 0.693

    9d = 0.077d1

    awi, †gŠj؇qi cÖv_wgK cigvYyi msL¨v N0 Ges Aewkó cigvYyi msL¨v N| AZGe, N = N0 Gi 40%| †gŠj؇qi ÿq n‡Z cÖ‡qvRbxq mgq, tA I tB n‡j,

    NN0

    = eAtA

    ev, 0.40 = e0.1155 tA

    tA = 7.93d

    NN0

    = eBtB

    ev, 0.44 = e0.077 tB

    tB = 11.9d

    †h‡nZz tB > tA, †m‡nZz DÏxc‡Ki †gŠj؇qi 56% ÿq n‡Z B †gŠ‡ji AwaK mgq jvM‡e|

    DËi: B Gi mgq †ewk jvM‡e|

    6 bs cÖ‡kœi DËi

    K gy³fv‡e †h‡Kvb Z‡j N~Y©‡b mÿg †Kvb Pz¤^K kjvKvi Aÿ †Kvb wbw`©ó ¯’v‡b Abyf‚wgK Z‡ji mv‡_ †h †Kv‡bv Drcbœ K‡i, ZvB

    webwZ|

    L †n·v‡Wwm‡gj c×wZ‡Z †gvU we‡Ui msL¨v 16 wU| A_©vr 24 | A_©vr †n·v‡Wwm‡gj c×wZi e„nËg weU (D) †K cÖKvk Ki‡Z evBbvix c×wZi 4 wU we‡Ui cÖ‡qvRb| GRb¨ evBbvix cÖwZ 4wU weU GK‡Î †n·v‡Wwm‡g‡ji GKwU we‡Ui mgZzj¨ gvb cvIqv hvq|

    GRb¨ †n·v‡Wwm‡gj c×wZ‡Z m‡e©v”P 4 weU cvIqv hvq|

    M DÏxc‡Ki eZ©bxwU bi-†MU (NOR-gate) Gi| GB †M‡Ui wPÎwU wb¤œiƒc :

    (NOR-gate) Gi mZ¨K mviYx

    BbcyU AvDUcyU

    A B C = A + B

    0 0 1

    1 0 0

    0 1 0

    1 1 0

    N DÏxc‡Ki eZ©bxi AvDUcy‡Ui mv‡_ GKwU bU †MU (NOT-gate) hy³ Ki‡j Ggb GKwU †MU cvIqv hv‡e hvi †h †Kvb GKwU BbcyU

    jwRK mZ¨ n‡j AvDUcyU jwRK mZ¨ n‡e| GB ai‡bi †MU‡K Ai

    (OR) †MU e‡j|

    A_©vr, NOR gate + NOT gate = OR gate.

    wb‡P Gi cÖZxK I Kvh©µg mZ¨K mviYxi gva¨‡g †`Lv‡bv n‡jv :

    mZ¨K mviwY

    BbcyU AvDUcyU

    A B C =

    A + B

    0 0 0

    0 1 1

    1 0 1

    1 1 1

    6. wm‡jU †evW©-2016

    1 bs cÖ‡kœi DËi

    K †Kvb cvZ AvKv‡ii Zworevnx cwievnK‡K †PŠ¤̂K‡ÿ‡Î j¤̂fv‡e ¯’vcb Ki‡j Zwor cÖevn I †PŠ¤̂K †ÿÎ Df‡qi mv‡_ j¤̂ eivei

    A_©vr cv‡Zi cÖ¯’ eivei GKwU wefe cv_©‡K¨i m„wó nq Z_v †fv‡ëR

    Drcbœ nq| GB NUbv‡K nj wµqv e‡j|

    C = A + B A B

    wPÎ: NOR gate

    A B

    A + B A + B

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    L UªvÝdg©v‡ii gyL¨ KzÐjx‡Z hw` DC †fv‡ëR cÖ‡qvR Kiv nq Zvn‡j †Kv‡ii ga¨ w`‡q aªæegv‡bi †PŠ¤̂Kd¬v· AwZµg Ki‡e|

    ZLb ddt = 0 nIqvq Zvwor †PŠ¤̂K Av‡ek msµvšÍ d¨viv‡Wi wØZxq

    m~Îvbymv‡i

    = – N

    ddt †MŠY KzÐjx‡Z Avweó ZworPvjK e‡ji gvb

    k~b¨| G Kvi‡Y UªvÝdg©vi Øviv DC †Wv‡ë‡Ri gvb cwieZ©b Kiv hvq

    bv|

    M GLv‡b,

    AC Dr‡mi we Í̄vi Z_v kxl©gvb, o = 220V

    Avgiv Rvwb, = 2f = 2 50 = 100

    Avevi †h †Kvb mgq t G kxl©gvb o Ges †KŠwYK †eM n‡j,

    = o sin t

    = 220 sin 100t

    A_©vr DÏxc‡Ki cwieZ©x Zwo”PvjK e‡ji mgxKiY,

    = 220 sin 100t (Ans.)

    N GLv‡b,

    AC Dr‡mi we Í̄vi, o = 220V

    wnUv‡ii †iva, R = 1000

    DC Dr‡mi wefe, Z_v Kvh©Ki †fv‡ëR, V = 220V

    AC Dr‡mi †ÿ‡Î,

    Kvh©Ki †fv‡ëR, rms = o

    2 =

    220

    2 = 155.56V

    Gwm Dr‡mi mv‡_ hy³ Ki‡j wnUv‡ii ÿgZv,

    P = 2rms

    R = (155.56)2

    1000 = 24.2 watt

    Avevi, wW. wm Dr‡mi mv‡_ hy³ Ki‡j ÿgZv,

    P = V2

    R = (220)2

    1000 = 48.4 watt

    †h‡nZz wW. wm Dr‡mi †ÿ‡Î wnUv‡ii ÿgZv †ewk, AZGe wW. wm

    Dr‡mi ms‡hv‡M wnUviwU †ewk Kvh©Ki|

    2 bs cÖ‡kœi DËi

    K †Kv‡bv †ZRw¯µq bgybvq cigvYy msL¨v †h mg‡q †f‡½ A‡a©‡K cwiYZ nq †m mgq‡K H †ZRw¯µq †gŠ‡ji Aa©vqy e‡j|

    L X-ray †Kvb AvwnZ KYv bq| GwU GKwU Zwor Pz¤^Kxq Zi½| †h‡nZz X-ray †Kvb PvwR©Z KYvi cÖevn bq, ZvB X-ray †PŠ¤̂K †ÿÎ I Zwor‡ÿÎ Øviv wePz¨Z nq bv|

    M GLv‡b,

    1g K‡ÿi e¨vmva©, r1 = 0.53A

    Kÿc_, n = 3,

    n Zg Kÿc‡_i e¨mva©, rn = ?

    Avgiv Rvwb,

    rn = n2.r1 = 32 0.53A = 4.77 A

    A_©vr 3q Kÿc‡_i e¨vmva© = 4.77 A (Ans.)

    N AvcwZZ †dvU‡bi kw³,

    E = hf

    = 6.63 10–34Js 2.46 1015 Hz

    = 1.631 10–18J = 10.2 eV

    nvB‡Wªv‡R‡bi cÖ_g Kÿc‡_ B‡jKUª‡bi kw³, E1 = – 13.6 eV

    wØZxq Kÿc‡_ B‡jKUª‡bi kw³, E2 = – 13.6

    22 eV

    = – 3.4 eV

    myZivs cÖ_g Kÿc_ †_‡K 2q Kÿc‡_ B‡jKUªb †h‡Z cÖ‡qvRbxq

    kw³,

    E = E2 – E1

    = – 3.4 eV – (– 13.6 eV)

    = 10.2 eV

    AvcwZZ †dvU‡bi kw³ = B‡jKUªbwU cÖ_g Kÿc_ †_‡K wØZxq Kÿc‡_ †h‡Z cÖ‡qvRbxq kw³

    myZivs B‡jKUªbwU wØZxq Kÿc‡_ Mgb Ki‡e|

    3 bs cÖ‡kœi DËi

    K †cÖvUb I wbDUªb¸‡jv‡K wbDwK¬qv‡m GK‡Î †e‡a ivL‡Z †h kw³i cÖ‡qvRb Zv‡K wbDwK¬qv‡mi eÜb kw³ e‡j|

    L m~h© K…ò wee‡i cwiYZ n‡j Gi AvKvi AZ¨šÍ †QvU n‡e wKš‘ f‡ii †Kvbiƒc cwieZ©b n‡e bv Ges m~‡h©i fi‡K›`ª †_‡K c„w_exi

    `~i‡Z¡i †Kv‡bv cwieZ©b n‡e bv| G‡Z m~h© I c„w_exi AvKl©Y e‡ji

    I †Kv‡bv cwieZ©b n‡e bv| d‡j c„w_ex m~‡h©i Pviw`‡K Nyi‡Z

    _vK‡e|

    M GLv‡b, avZe `‡Ûi,

    w¯’wZkxj ˆ`N©̈ , Lo = 1m

    †eM, v = 0.9c

    MwZkxj ˆ`N©̈ , L= ?

    Avgiv Rvwb,

    L = Lo 1 – v2

    c2

    = 1 1 –

    0.9c

    c

    2

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    = 1 1 – 0.81

    = 0.435m

    MwZkxj KvVv‡gv‡Z avZe e ‘̄wUi ˆ`N©̈ = 0.435m (Ans.)

    N GLv‡b, †eM, v = 0.9c

    w¯’wZkxj ˆ`N©̈ , Lo = 1m

    MwZkxj ˆ`N©̈ , L = 0.435m [M †_‡K]

    w¯’wZkxj Ae¯’vi NbZ¡, o = 19.3 103 kgm–3

    MwZkxj Ae ’̄vq NbZ¡, = ?

    †h‡nZz `ÛwU‡K cvebx ˆ`N©¨ eivei MwZkxj K‡ib AZGe ˆ`N©¨

    eiveiB ïay ms‡KvPb n‡e|

    awi, `‡Ûi cÖ¯’‡”Q‡`i †ÿÎdj = A

    Avgiv Rvwb, m = mo

    1 – v2

    c2

    wKš‘ m = V

    V = oVo

    1 – v2

    c2

    ev, AL = oALo

    1 – v2

    c2

    ev, L = oLo

    1 – v2

    c2

    ev, = 19.3 103 1

    0.435 1 –

    0.9c

    c

    2

    = 101.78 103 kgm–3

    A_©vr, > o cvebx e ‘̄wUi NbZ¡ nvmvb mv‡ne A‡cÿv †ewk cv‡e|

    4 bs cÖ‡kœi DËi

    K †h †Kvb ỳwU Avav‡bi g‡a¨ wbw`©ó `~i‡Z¡ k~b¨¯’v‡b wµqvkxj ej Ges H ỳB Avav‡bi g‡a¨ GKB ~̀i‡Z¡ Ab¨ †Kvb gva¨‡g wµqvkxj

    e‡ji AbycvZ‡K H gva¨‡gi civ ˆe`y¨wZK aªæeK e‡j|

    L Zwor cÖev‡ni mgq Zwor e‡ji cÖfv‡e Gi wfZ‡ii gy³ B‡jKUªb¸‡jvi †eM e„w× cvq Avevi cwievnxi cigvYyi mv‡_

    av°vRwbZ evavi d‡j †eM n«vm cvq| G evavB cwievwni †iva|

    ZvcgvÎv e„wׇZ AYy¸‡jvi K¤úb e„w× cvq, d‡j Gi ga¨ w`‡q

    cÖevwnZ B‡jKUª‡bi msNl© msL¨v e„w× cvq, ZvB ZvcgvÎv e„wׇZ

    cwievwni †iva e„w× cvq|

    M GLv‡b, Awfj‡ÿ¨i †dvKvm ~̀iZ¡, fo = 0.02m

    Awf‡b‡Îi †dvKvm ~̀iZ¡, fe = 0.07m

    Awfj‡ÿ¨i e ‘̄i ~̀iZ¡, uo = 0.023m

    weea©b, M = ?

    Avgiv Rvwb,

    1vo

    + 1uo

    = 1fo

    ev, 1vo

    = 1fo

    – 1uo

    ev, 1vo

    = 1

    0.02m – 1

    0.023m

    ev, vo = 0.153m

    Avevi, weea©b,

    M = – vouo

    1 +

    Dfe

    [D = 0.25m †h‡nZz †Mvjv‡ci †PvL

    ÎæwUnxb Ges P‚ovšÍ we¤^ Aev Í̄e]

    = – 0.153m 0.023m

    1 +

    0.25m0.07m = – 30.4

    A_©vr †Mvjvc 30.4 ¸Y weewa©Z we¤^ †`L‡Z cv‡e| (Ans.)

    N ÔMÕ †_‡K,

    Awfj‡ÿ¨i we‡¤^i ~̀iZ¡, vo = 0.153m

    Awf‡b‡Îi †dvKvm ~̀iZ¡, fe = 0.07m

    †Mvjv‡ci Rb¨,

    Awf‡b‡Îi we‡¤̂i ~̀iZ¡, ve = – 0.25m

    Awf‡b‡Îi e ‘̄i ~̀iZ¡, ue = ?

    h‡š¿i ˆ`N©̈ , L = ?

    Avgiv Rvwb, 1ve

    + 1ue

    = 1fe

    ev, 1ue

    = 1fe

    – 1ve

    ev, 1ue

    = 1

    0.07m + 1

    0.25m

    ev, ue = 0.054 m

    h‡š¿i ˆ`N©¨, L = vo + ue = 0.153 m + 0.054m = 0.207m

    AvRv‡`i Rb¨,

    Awf‡b‡Îi we‡¤̂i ~̀iZ¡, ve = – 0.4m

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    1ve

    + 1ue

    = 1fe

    ev, 1ue

    = 1fe

    – 1ve

    = 1

    0.07m – 1

    – 0.4m

    ev, 1ue

    = 1

    0.07m + 1

    0.4m

    ue = 0.059m

    h‡š¿i ˆ`N©¨, L = vo + ue = 0.153m + 0.059m = 0.212m

    A_©vr ø̄vBW ch©‡eÿ‡Y Df‡qi †ÿ‡Î h‡š¿i ˆ`N©¨ GKB wQj bv|

    5 bs cÖ‡kœi DËi

    K †Kvb GKwU KzÛjx‡Z Zwor cÖevn cwieZ©b Ki‡j wbKUeZ©x Ab¨ GKwU KzÛjx‡Z †h Zvwor †PŠ¤̂K Av‡ek m„wó nq Zv‡K cvi¯úwiK

    Av‡ek e‡j|

    L †Kvb cwievn‡Ki cwievnxZv 0.2 wm‡gÝ ej‡Z †evSvq †h, H cwievn‡Ki ỳB cÖv‡šÍi wefe cv_©K¨ 1V n‡j Zvi ga¨ w`‡q 0.2A

    Zwor cÖevn P‡j| wm‡gÝ cwievnxZvi GKK hv †iv‡ai GKK Ing

    Gi wecixZ ivwk|

    M GLv‡b, Zwor cÖevn, I = 4A

    Zvi †_‡K ~̀iZ¡, a = 0.16m

    o = 4 10–7 TmA–1

    H we›`y‡Z †PŠ¤^K‡ÿÎ, B = ?

    Avgiv Rvwb,

    †mvRv Zv‡ii Rb¨,

    B = oI

    2a =

    4 10–7 4

    2 0.16 = 5 10–6T

    ZviwU n‡Z 0.16m ~̀‡i †PŠ¤̂K‡ÿ‡Îi gvb 5 10–6T (Ans.)

    N †mvRv Zv‡ii Rb¨ †PŠ¤̂K‡ÿÎ, B = 5 10–6T

    GLb ZviwU‡K †cuwP‡q GK cv‡Ki e„ËvKvi KzÛjx‡Z cwiYZ Ki‡j,

    2r1 = 2

    ev, r1 = 1

    = 0.318m

    Ges o = 4 10–7 TmA–1

    I = 4A

    GK cv‡Ki e„ËvKvi KzÛjxi †K‡›`ª †PŠ¤̂K‡ÿÎ,

    B = oI2r1

    = 4 10–7 4

    2 0.318 = 7.89 10–6T

    hv †mvRv Zv‡ii †PŠ¤̂K‡ÿ‡Îi †P‡q †ewk A_©vr B > B

    Avevi, †cwP‡q N = 10 cv‡Ki KzÛjx ˆZwi Ki‡j

    2r2 N = 2

    ev, r2 = 1

    N =

    r1N

    eZ©gv‡b †K‡› ª̀ †PŠ¤^K‡ÿÎ, B = oNI2r2

    B

    B = oNI2r2

    2r101

    = Nr1r2

    = Nr1r1N

    = N2 = 102 = 100

    B = 100 B

    myZivs DÏxc‡Ki e³e¨ mwVK|

    6 bs cÖ‡kœi DËi

    K †h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b K‡i Ges m¤§yLeZx© I wecixZgyLx cÖwµqvi cÖwZ ¯Í‡i Zvc I Kv‡Ri djvdj mgvb I

    wecixZ nq †mB cÖwµqv‡K cÖZ¨vMvgx cÖwµqv e‡j|

    L Kv‡b©v BwÄb Øviv Kv‡R iƒcvšÍwiZ Zvckw³ I BwÄb Øviv †kvwlZ Zvckw³i AbycvZ‡K Kv‡b©v Bwćbi `ÿZv e‡j| Kv‡b©v Bwćbi

    `ÿZv, = T1 – T2

    T1 100% mgxKi‡Y, T1 n‡jv Dr‡mi ZvcgvÎv

    Ges T2 MÖvn‡Ki ZvcgvÎv| D³ mgxKiY Abymv‡i, T2 Gi gvb hZ

    n«vm cv‡e, (T1 – T2) Gi gvb ZZ e„w× cv‡e| T1 – T2 Gi gvb hZ

    evo‡e Kv‡b©v Bwćbi `ÿZv ZZ evo‡e| G Kvi‡Y ZvcMÖvn‡Ki

    ZvcgvÎv n«vm †c‡j Kv‡b©v Bwćbi `ÿZv e„w× cvq|

    M DÏxcK Abymv‡i, = 1.33

    cÖv_wgK ZvcgvÎv, T1 = 27C = (273 + 27) K

    = 300 K

    cÖv_wgK Pvc, P1 = 1 evqygÐjxq Pvc

    P‚ovšÍ Pvc, P2 = 2 evqygÐjxq Pvc

    P‚ovšÍ ZvcgvÎv, T2 = ?

    Avgiv Rvwb, T1P1

    1 –

    = T2P2

    1 –

    ev, T2 = T1 P1

    P2

    1 –

    = 300 1

    2

    1 – 1.331.33

    = 356.297 K

    = 83.297C (Ans.)

    N DÏxcK Abymv‡i,

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    cÖv_wgK NbZ¡, 1 = 100 kgm–3

    cÖv_wgK ZvcgvÎv, T1 = 27C = 300 K

    cÖv_wgK Pvc, P1 = 1 evqygÐjxq Pvc

    P‚ovšÍ Pvc, P2 = 2 evqygÐjxq Pvc

    ÔMÕ Ask n‡Z cvB,

    P‚ovšÍ ZvcgvÎv, T2 = 356.297 K

    P‚ovšÍ NbZ¡, 2 = ?

    Nb‡Z¡i cwieZ©b, = ?

    Avgiv Rvwb,

    1T1P1

    = 2T2P2

    ev, 2 = 1 T1 P2

    P1 T2

    = 100 300 2

    1 356.297

    = 168.4 kgm–3

    = (2 – 1)

    = (168.4 – 100) kgm–3

    = 68.4 kgm–3

    AZGe, †P¤̂viwUi P‚ovšÍ ZvcgvÎvq M¨v‡mi NbZ¡ 68.4 kgm–3 e„w× cv‡e|

    7. h‡kvi †evW©-2016

    1 bs cÖ‡kœi DËi

    K †Kvb wm‡÷‡gi kw³ iƒcvšÍ‡ii AÿgZv ev Am¤¢ve¨Zv‡K ev iƒcvšÍ‡ii Rb¨ kw³i AcÖvßZv‡K GbUªwc e‡j|

    L ỳwU e ‘̄i Zvc aviY ÿgZv wfbœ nIqvi Kvi‡Y GKB cwigvY Zvc ỳwU wfbœ e¯‘‡Z mieivn Kiv n‡jI ZvcgvÎvi cwigvY wfbœ

    nq|

    Zvc n‡jv e ‘̄‡Z kw³i cwigvc wKš‘ ZvcgvÎv n‡jv e ‘̄i Af¨šÍixY

    AYymg~‡ni MZxq Aw¯’iZv| wfbœ wfbœ e¯‘i AvšÍtAvYweK MVb wewfbœ

    nIqvi Kvi‡Y GKB Zvc w`‡j I ZvcgvÎvi cwigvY wfbœ n‡Z cv‡i|

    M GLv‡b, D”P ZvcgvÎv, T1 = 327C = 600K

    wb¤œ ZvcgvÎv, T2 = 27C = 300K

    Zvc Drm †_‡K M„nxZ Zvc, Q1 = 6000 J

    Zvc MÖvn‡K ewR©Z Zvc, Q2 = ?

    Avgiv Rvwb, Q1T1

    = Q2T2

    ev, Q2 = Q1T2

    T1

    = (6000 J) (300 K)

    (600 K) = 3000 J (Ans.)

    N GLv‡b,

    cÖ_g †ÿ‡Î,

    D”P ZvcgvÎv, T1 = 327C = 600 K

    wb¤œ ZvcgvÎv, T2 = 27C = 300 K

    Kg©`ÿZv, 1 = ?

    Avgiv Rvwb,

    1 = 1 – T2T1

    = 1 – 300 K600 K = 0.5

    GLv‡b,

    wØZxq †ÿ‡Î Kg©`ÿZv, 2 = 21 = 2 0.5 = 1

    Zvn‡j, D”P ZvcgvÎv, T1 = 600 K

    wb¤œ ZvcgvÎv, T2 = ?

    Avgiv Rvwb,

    2 = 1 – T2

    T1

    ev, T2

    T1 = 1 – 2

    ev, T2 = (1 – 2) T1

    = (1 – 1) 600 K

    = 0 K

    †h‡nZz `ÿZv wظY Ki‡j Zvc MÖvn‡Ki ZvcgvÎv 0 K Ki‡Z nq hv ev Í̄‡e m¤¢e bq| ZvB Kg©`ÿZv wظY Kiv m¤¢e bq|

    2 bs cÖ‡kœi DËi

    K cÖwZ GKK Avavb‡K †Kvl m‡gZ †Kvb eZ©bxi GK we›`y †_‡K m¤ú~Y© eZ©bx Nywi‡q Avevi H we› ỳ‡Z Avb‡Z †h KvR m¤úbœ nq

    A_©vr †Kvl †h Zwor kw³ mieivn K‡i Zv‡K H †Kv‡li Zwo”PvjK

    kw³ e‡j|

    L Zwor cwievn‡K †ek wKQy msL¨K gy³ B‡jKUªb _v‡K| cwievn‡Ki ỳB we›`yi g‡a¨ wefe cv_©K¨ m„wó n‡j gy³

    B‡jKUªb¸‡jv AvšÍtAvYweK ’̄v‡bi ga¨w`‡q cwievn‡Ki wb¤œ wefe

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    †_‡K D”P wef‡ei w`‡K Pj‡Z _v‡K, d‡j Zwor cÖev‡ni m„wó nq|

    GB B‡jKUªb¸‡jv Pjvi mgq cwievn‡Ki cigvYyi mv‡_ msN‡l© wjß

    nq Ges B‡jKUª‡bi MwZkw³ cigvYy‡Z mÂvwjZ nq Ges cigvYyi

    MwZkw³ Av‡iv e„w× cvq| GB ewa©Z MwZkw³ Zv‡c iƒcvšÍwiZ nq|

    GRb¨ Zwor cÖev‡ni d‡j eZ©bx‡Z Zv‡ci D™¢e nq|

    M GLv‡b,

    cÖ_g †Mvj‡Ki e¨vmva©, r1 = 0.2 m

    cÖ_g †Mvj‡Ki wefe, V1 = 5V

    †MvjKwUi PvR©, q1 = ?

    1

    4o = 9 109 Nm2C–2

    Avgiv Rvwb, †Mvj‡Ki wefe

    V1 = 1

    4o q1r1

    ev, q1 = V1r1

    1

    4o

    = (5V) (0.2 m)

    (9 109 Nm2C–2)

    = 1.11 10–10C (Ans.)

    N GLv‡b,

    wØZxq †Mvj‡Ki e¨vmva©, r2 = 0.3 m

    wØZxq †Mvj‡Ki wefe, V2 = 10 V

    †MvjKwUi PvR©, q2 = ?

    Avgiv Rvwb,

    V2 = 1

    4o q2r2

    ev, q2 = V2r2

    1

    4o

    = (10 V) (0.3 m)

    (9 109 Nm2C–2)

    = 3.33 10–10 C

    awi,

    cÖ_g †MvjK n‡Z x ~̀i‡Z¡ A we›`y‡Z cÖvej¨ k~b¨ n‡e|

    A_©vr, E1 = E2 n‡e|

    GLv‡b, E1 = 1

    4o q1x2

    ev, E1 = (9 109 Nm2C–2) 1.11 10–10 C

    x2

    Avevi, E2 = 1

    4o

    q2(1 – x)2

    ev, E2 = (9 109 Nm2C–2) (3.33 10–10 C)

    (1 – x)2

    GLb, E1 = E2

    ev, 1.11 10–10 C

    x2 = (3.33 10–10 C)

    (1 – x)2

    ev, (1 – x)2

    x2 = 3.33 10–10 C

    1.11 10–10 C

    ev,

    1 – x

    x2 = 3

    ev, 1 – x

    x = 3

    ev, 1x – 1 = 3

    ev, 1x = 3 + 1

    ev, x = 1

    3 + 1

    = 0.37 m

    A_©vr, cÖ_g †MvjKwU †_‡K 0.37 m ~̀i‡Z¡ cÖvej¨ k~b¨ n‡e|

    3 bs cÖ‡kœi DËi

    K ZvcgvÎv e„w× Ki‡Z _vK‡j †h ZvcgvÎvq †Kv‡bv †d‡iv-†PŠ¤̂K c`v_© c¨viv‡PŠ¤^K c`v‡_© cwiYZ nq Zv‡K H †d‡iv‡PŠ¤̂K c`v‡_©i

    Kzixwe›`y e‡j|

    L †KŠwYK †e‡Mi cwieZ©‡bi Kvi‡Y N~Y©vqgvb B‡jKUª‡bi Kÿxq †PŠ¤^K †gv‡g›UI cwiewZ©Z nq| †KŠwYK †eM n«vm †c‡j †PŠ¤^K

    †gv‡g‡›Ui gvb n«vm cvq, Avi †eM e„w× n‡j †gv‡g‡›Ui gvb ev‡o|

    myZivs, †`Lv hv‡”Q †h Wvqv‡PŠ¤̂K c`v‡_©i Dci †PŠ¤̂K‡ÿÎ

    B cÖ‡qvM Ki‡j GKwU †PŠ¤̂K †gv‡g›U Avweó nq Ges Gi AwfgyL

    ewnt ’̄ †PŠ¤̂K‡ÿÎ

    B Gi wecixZ, d‡j weKl©Y nq| ZvB Wvqv‡PŠ¤̂K c`v_© †PŠ¤^K c`v_© nIqv m‡Ë¡I Pz¤^K Øviv weKwl©Z nq|

    M GLv‡b,

    KzÐjxi ˆ`N©¨, L = 3 cm = 3 10–2m

    KzÐjxi cÖ¯’, b = 2 cm = 2 10–2m

    KzÐjxi †ÿÎdj, A = Lb

    = (3 10–2m) (2 10–2m)

    = 6 10–4m2

    KzÐjxi cvK msL¨v, N = 1

    E1 = A

    x 1

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    cÖevn, I = 2A

    †PŠ¤^K‡ÿÎ, B = 1.5 103 Am–1

    KzÐjxZj †PŠ¤̂K‡ÿ‡Îi mv‡_ j¤̂ n‡j, Zj †f±i †PŠ¤̂K †ÿ‡Îi

    mgvšÍivj nq, †m‡ÿ‡Î = 0 n‡e

    wµqvkxj UK©, = ?

    Avgiv Rvwb,

    = NIAB sin

    = 1 (2A) (6 10–4m2) (1.5 103 Am–1) (sin 0)

    = 0 (Ans.)

    N GLv‡b, KzÐjxi †ÿÎdj, A = 6 10–4m2

    KzÐjxwU †PŠ¤^K‡ÿ‡Îi Z‡ji mv‡_ 90 †Kv‡Y wewÿß n‡j K…Z KvR

    n‡e,

    W =

    o

    /2

    d

    =

    o

    /2

    NIAB sin d

    = NIAB

    o

    /2

    sin.d

    = NIAB [–cos]0/2

    = NIAB [–cos /2 + cos 0]

    = NIAB [0 + 1]

    = NIAB

    = 1 2 6 10–4 1.5 103

    = 1.8 J

    1.8 J KvR Ki‡Z n‡e| (Ans.)

    4 bs cÖ‡kœi DËi

    K Av‡jv †Kv‡bv gva¨‡gi ga¨ w`‡q Mg‡bi ci Av‡jvK Zi‡½i K¤úb GKwU wbw ©̀ó Z‡j nIqvi NUbv‡K Av‡jvi mgeZ©b e‡j|

    L ỳwU Drm †_‡K mg`kvq ev †Kvb wbw`©ó `kv cv_©‡K¨i GKB Zi½‰`‡N©¨i `ywU Av‡jvK Zi½ wbtm„Z n‡j Zv‡`i mymsMZ Drm

    e‡j| mvaviYZ ỳwU Avjv`v Drm‡K mymsMZ Drm wn‡m‡e MY¨ Kiv

    hvq bv, †Kbbv †Kvb Dr‡mi wbtm„Z Av‡jv Ab¨ Dr‡mi Dci †Kvb

    fv‡eB wbf©i K‡i bv| ZvB Avjv`v ̀ ywU Drm GKwU wbw`©ó ̀ kv m¤úK©

    eRvq ivL‡Z cv‡i bv| d‡j G‡`i g‡a¨ Zi½ ˆ`N©¨ I we¯Ív‡i †ek

    cv_©K¨ †`Lv hvq| ZvB cÖK…wZ‡Z †Kvb mymsMZ Drm †bB|

    M GLv‡b, cÖwZmviK †KvY, A = 60

    cÖwZmiv¼, = 2

    b~¨bZg wePz¨wZ †KvY, m = ?

    Avgiv Rvwb, =

    sin

    A + m

    2

    sin A2

    ev, 2 =

    sin

    60 + m

    2

    sin 60

    2

    ev, sin

    60 + m

    2 = 2 sin 30 = 2 12 =

    1

    2 = sin 45

    ev, 60 + m

    2 = 45

    ev, m = 30 (Ans.)

    N GLv‡b, wcÖR‡gi cÖwZmviK †KvY, A = 60

    Avgiv Rvwb, †Kvb wcÖR‡gi wePz¨wZ †KvY,

    = i1 + i2 – A

    wKš‘ b~¨bZg wePz¨wZ Ae¯’v‡b, = m Ges i1 = i2

    AZGe,

    m = i1 + i2 – A

    ev, m = 2i1 – A

    ev, 2i1 = m + A

    ev, i1 = m + A

    2

    ev, i1 = 30 + 60

    2 [M bs n‡Z]

    ev, i1 = 45 = cÖ_g AvcZb †KvY

    AZGe, MvwYwZK we‡køl‡Y †`Lv hvq †h, wcÖR‡gi b~¨bZg wePz¨wZ

    Ae¯’v‡b cÖ_g AvcZb †KvY (i1) wbY©q Kiv m¤¢e Ges cÖ_g AvcZb

    †Kv‡Yi gvb 45|

    5 bs cÖ‡kœi DËi

    K cwievnxZv e„w×i D‡Ï‡k¨ Aa©cwievnx‡Z mvgvb¨ cwigvY myweavRbK wbw ©̀ó †gŠwjK c`v_© †fRvj †`qv nq| †fRvj c`v‡_©i

    ev®ú DËß Ae ’̄vq weï× Aa©cwievnxi ga¨ w`‡q Pvjbv K‡i †fRvj

    †`qvi c×wZ‡K †Wvwcs ejv nq|

    L nvB‡Rbev‡M©i AwbðqZv bxwZi m~Î

    xP

    h

    2 e¨envi K‡i

    wbw`©ó MvwYwZK we‡køl‡Y cvIqv hvq †h, B‡jKUª‡bi wbDwK¬qv‡mi

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    Af¨šÍ‡i _vK‡Z n‡j G‡K 37.6 MeV kw³i AwaKvix n‡Z n‡e|

    wKš‘ cixÿvjä djvdj †_‡K †`Lv hvq †h, B‡jKUª‡bi kw³ 4 MeV

    Gi AwaK nq bv| myZivs wbDwK¬qv‡mi Af¨šÍ‡i B‡jKUªb _vK‡Z

    cv‡i bv|

    M GLv‡b,

    AvcwZZ Av‡jvi Zi½‰`N©¨, = 2500 A

    = 2500 10–10 m

    avZzi Kvh©v‡cÿK, = 2.3 eV

    = 2.3 1.6 10–19 J

    = 3.68 10–19 J

    Av‡jvi ª̀æwZ, c = 3 108 ms–1

    cø̈ v¼ aªæeK, h = 6.63 10–34 Js

    d‡UvB‡jKUª‡bi m‡e©v”P MwZ‡eM, vmax = ?

    B‡jKUª‡bi fi, m = 9.1 10–31 kg

    Avgiv Rvwb,

    h = Kmax +

    ev, h = 12 m(vmax)

    2 +

    ev, 12 m(vmax)

    2 = h –

    ev, 12 m(vmax)

    2 = hc

    ev, 12 m(vmax)

    2 = (6.63 10–34 Js) (3 10ms–1)

    (2500 10–10m) – (3.68 10–19

    J)

    ev, 12 m(vmax)

    2 = 4.28 10–19 J

    ev, vmax = 2 (4.28 10–19J)

    m

    = 2 4.28 10–19J

    9.1 10–31 kg

    = 9.7 105 ms–1 (Ans.)

    N GLv‡b,

    Kvh©v‡cÿK, = 2.3 eV

    = 3.68 10–19 J

    cøv‡¼i aªæeK, h = 6.63 10–34 Js

    m~Pb K¤úv¼, o = ?

    Avgiv Rvwb,

    = hf0

    ev, 0 =

    h

    = 3.68 10–19J

    6.63 10–34 J

    = 5.55 1014 Hz

    Avevi,

    AvcwZZ iwk¥i Zi½ ˆ`N©¨, = 5897A

    = 5897 10–10m

    K¤úv¼, = ?

    Avgiv Rvwb,

    c =

    ev, = c

    = 3 108 ms–1

    5897 10–10m = 5.09 1014 Hz

    A_©vr, K¤úv¼ , m~Pb K¤úvsK o A‡cÿv ÿz`ªZi ( < o)| A_©vr

    5897A Zi½‰`‡N©̈ i Av‡jvi Rb¨ B‡jKUªb gy³ n‡e bv|

    6 bs cÖ‡kœi DËi

    K †Kvb Ro KvVv‡gv‡Z msNwUZ ỳwU NUbvi ga¨eZx© mgq e¨eavb A‡cÿv H KvVv‡gvi mv‡c‡ÿ MwZkxj †Kvb Ro KvVv‡gv‡Z

    cwigvcK…Z GKB NUbv؇qi ga¨eZx© mgq e¨eavb †ewk nq| G‡KB

    Kvj `xN©vqb e‡j|

    L weï× Aa©cwievnx B‡jKUªwb· G †Kv‡bv Kv‡R jv‡M bv| ZvB weï× Aa©cwievnx‡Z mvgvb¨ cwigvY myweavRbK †gŠwjK c`v_©

    mywbqwš¿Z fv‡e †fRvj w`‡j Gi cwievnxZv e„w× cvq| mvaviYZ ̀ yB

    ai‡bi †fRvj w`‡q P UvBc I n UvBc Aa©cwievnx ˆZwi Kiv nq|

    P-N Rskb I UªvbwR÷i B‡jKUªwb‡·i mKj Kv‡R e¨en„Z nq|

    M GLv‡b,

    †ZRw¯µq X-cigvYyi Mo Avqy, = 2294 eQi

    Aa©vqy, T12

    = ?

    Avgiv Rvwb,

    T12

    = 0.693 = 0.693 2294 eQi = 1589.742 eQi| (Ans.)

    N GLv‡b,

    †ZRw®µq X-cigvYyi Mo Avqy, = 2294 eQi

    Aeÿq aªæeK, = ?

    Avgiv Rvwb,

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    = 1

    ev, = 1

    2294 eQi

    = 4.36 10–4 y–1

    GLb, hLb, N1 = 0.5 No ZLb mgq t1 n‡j,

    N1 = No e–t1

    ev, 0.5 No = No e–t1

    ev, 0.5 = e–t1

    ev, n (0.5) = –t1

    ev, t1 = – n(0.5)

    = – n(0.5)

    (4.36 10–4 y–1)

    = 1589.742 y = T12

    (M bs †_‡K)

    Avevi, hLb, N2 = 0.25No ZLb mgq t2 n‡j,

    t2 = – n(0.25)

    = 3179.57 yr = 2 T1

    2

    Avevi, N3 = 0.125No Gi Rb¨ mgq t3 n‡j,

    t3 = – n(0.125)

    = 4768.36 yr = 3 T1

    2

    A_©vr, †jLwPÎwU †ZRw¯µq ÿq m~Î †g‡b P‡j|

    8. ewikvj †evW©-2016

    1 bs cÖ‡kœi DËi

    K †h cÖwµqv wecixZgyLx n‡q cÖZ¨veZ©b K‡i Ges m¤§yLeZx© I wecixZgyLx cÖwµqvi cÖwZ ¯Í‡i Zvc I Kv‡Ri djvdj mgvb I

    wecixZ nq †mB cÖwµqv‡K cÖZ¨vMvgx cÖwµqv e‡j|

    L Kv‡b©v BwÄb Øviv Kv‡R iƒcvšÍwiZ Zvckw³ I BwÄb Øviv †kvwlZ Zvckw³i AbycvZ‡K Kv‡b©v Bwćbi `ÿZv e‡j| Kv‡b©v Bwćbi

    `ÿZv, = T1 – T2

    T1 100% mgxKi‡Y, T1 n‡jv Dr‡mi ZvcgvÎv

    Ges T2 MÖvn‡Ki ZvcgvÎv| D³ mgxKiY Abymv‡i, T2 Gi gvb hZ n«vm cv‡e, (T1 – T2) Gi gvb ZZ e„w× cv‡e| T1 – T2 Gi gvb hZ evo‡e Kv‡b©v Bwćbi `ÿZv ZZ evo‡e| G Kvi‡Y ZvcMÖvn‡Ki

    ZvcgvÎv n«vm †c‡j Kv‡b©v Bwćbi `ÿZv e„w× cvq|

    M DÏxcK Abymv‡i, = 1.33

    cÖv_wgK ZvcgvÎv, T1 = 27C = (273 + 27) K

    = 300 K

    cÖv_wgK Pvc, P1 = 1 evqygÐjxq Pvc

    P‚ovšÍ Pvc, P2 = 2 evqygÐjxq Pvc

    P‚ovšÍ ZvcgvÎv, T2 = ?

    Avgiv Rvwb,

    T1P1

    1 –

    = T2P2

    1 –

    ev, T2 = T1 P1

    P2

    1 –

    = 300 1

    2

    1 – 1.331.33

    = 356.297 K

    = 83.297C (Ans.)

    N DÏxcK Abymv‡i,

    cÖv_wgK NbZ¡, 1 = 100 kgm–3

    cÖv_wgK ZvcgvÎv, T1 = 27C = 300 K

    cÖv_wgK Pvc, P1 = 1 evqygÐjxq Pvc

    P‚ovšÍ Pvc, P2 = 2 evqygÐjxq Pvc

    ÔMÕ Ask n‡Z cvB,

    P‚ovšÍ ZvcgvÎv, T2 = 356.297 K

    P‚ovšÍ NbZ¡, 2 = ?

    Nb‡Z¡i cwieZ©b, = ?

    Avgiv Rvwb,

    1T1P1

    = 2T2P2

    ev, 2 = 1 T1 P2

    P1 T2

    = 100 300 2

    1 356.297

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  • c`v_©weÁvb wØZxq cÎ: m„Rbkxj cÖ‡kœi mgvavb

    c`v^Æweævb

    = 168.4 kgm–3

    = (2 – 1)

    = (168.4 – 100) kgm–3

    = 68.4 kgm–3

    AZGe, †P¤̂viwUi P‚ovšÍ ZvcgvÎvq M¨v‡mi NbZ¡ 68.4 kgm–3 e„w× cv‡e|

    2 bs cÖ‡kœi DËi

    K wZb †mŠi f‡ii mgvb ev †ewk f‡ii bÿ‡Îi mycvi †bvfv we‡ùvi‡Yi ci Gi AšÍe©¯‘ Awb©wÏófv‡e msKzwPZ n‡Z _v‡K|

    ms‡KvP‡bi Kvi‡Y AvqZb cÖvq k~b¨ Ges NbZ¡ Amxg nIqvq gnvKl©

    †ÿÎ Ggb cÖej nq †h, G RvZxq e¯‘ †_‡K Gi gnvKl©‡K KvwU‡q

    †Kvb cÖKvi Av‡jv GgbwK ms‡KZI †ewi‡q Avm‡Z cv‡i bv| ZvB

    e¯‘wU‡K Avi †`Lv hvq bv| bÿ‡Îi GB Ae ’̄v‡K ejv nq K…ò

    MnŸi|

    L ci¯ú‡ii mv‡c‡ÿ aªæe‡e‡M MwZkxj †h mKj cÖm‡½ KvVv‡gv‡Z wbDU‡bi MwZm~Î AR©b Kiv hvq Zv‡`i‡K Ro cÖm½ KvVv‡gv e‡j|

    N~Y©bkxj e¯‘i †eM cÖwZwbqZ cwiewZ©Z nq e‡j GwU aªæe‡e‡M

    MwZkxj bq A_©vr N~Y©bkxj e ‘̄i Z¡iY _v‡K| Avgiv Rvwb †h mKj

    cÖm½ KvVv‡gvi Z¡iY _v‡K Zv‡`i‡K ARo cÖm½ KvVv‡gv e‡j| G

    Kvi‡Y N~Y©bkxj KvVv‡gv Ro cÖm½ KvVv‡gv bq| eis GwU ARo

    cÖm½ KvVv‡gv|

    M DÏxcK n‡Z cvB,