Unit 10 MECHANIC OF PROPERTIES OF MATTER

Viscosity

(1) a,2a MiuAila xNugjhu;j;jj;jpyhd jpz;kf;Nfhsq;fs; Fwpj;j ghapapDs; RahjPdkhf ,aq;fmDkjpf;fg;gLfpd;wJ. rpwpa Nfhsk; vLf;Fk; KbTNtfk; V0 vdpd; nghpa Nfhsk; vLf;Fk; KbTNtfk; ahJ

(1) V0 (2) 2V0 (3) 3V0 (4) 4V0 (5) 8V0

(2019/New&Old/11)

(2)

R,2R,3R MiufSila jpz;kf;Nfhsq;fspd; jpzpTfs; rkd;. 3R Miu cila NfhskhdJ jputk; xd;wpy; tplg;gl Kw;WKOjhf mkpo;e;J rkdpiyapy; ,Ue;jJ. R,2R MiufSila Nfhsq;fs; mj;jputj;jpy; ,aq;ftplg;gl R MiuAila Nfhsk; Vo KbT Ntfj;ij vLj;jJ. 2R MiuAila Nfhsk; vLf;Fk; KbTNtfk; ahJ?

(2016/46)

(3) a MiuAk; jd;dPh;g;G 8 IAKila jpz;kf;Nfhsnkhd;W ePupDs; tpotplg;gLk; NghJ mjd;KbTf;fjp; v MftpUg;gpd; gpd;tUk; $w;Wf;fSs; jtwhdJ1. NfhskhdJ KbTf;fjpapy; ,aq;Fk; NghJ mjd; kPJ njhopw;gLk; tpisAs; tpir

g+r;rpakhFk;2. mNj gjhHj;jj;jhyhd mNj MiuAila nghl;Nfhsnkhd;iw ePupDs; ,aq;f

mDkjpf;fg;gl mJ fPo;Nehf;fp ,aq;fpd; KbTf;fjp v ,Yk; FiwthFk3. ,j;jpz;kf; Nfhsj;ij Njq;fha;vz;nzapDs; tpotplg;gLk; NghJ mjd; KbTf;fjp v ,Yk;

FiwthFk;4. ,j;jpz;kf; Nfhsj;ij ruhlh;j;jp 2 Ak; ePupd; ghFikf;Fzfj;jpd; ,Uklq;F

ghFikf;Fzfj;ijAKila jputnkhd;wpy; tpotplg;gLk; NghJ mjd; KbTf;fjp v MFk;5. 2a MiuAila mNj gjhHj;jj;jhyhd jpz;kf;Nfhsj;ij ePpupDs; tpotpLk; NghJ mjd;

KbTf;fjp 4v MFk;.(2015/20)

kPspay;G

(4) neLQ;rhiy xd;wpy; nfhq;fpwPw; fw;fs; xd;Wf;nfhd;W ve;j ,ilntspAk; ,y;yhJxd;Wlndhd;W kpf neUf;fkhf mLf;fp itf;fg;gl;Ls;sd. ,jd; fhuzkhf ,it tpuptilaKbahJs;sJ. Fsph; fhyk; xd;wpy; mjhtJ ntg;gepiy 8 0C MfTs;s ehs; xd;wpy;,e;neLQ;rhiyapd; fl;Lkhd Ntiyfis Nkw;nfhz;l egh;fspdhy; ,f;fw;fs; Nkw;$wpathWmLf;fg;gl;ld. #lhd ehs; xd;wpy; mjhtJ ntg;gepiy 380C Mf cs;s re;jh;g;gj;jpy;fw;fs; kPjhd jifg;G ahJ? nfhq;fpwPw;wpd; neUf;fYf;fhd aq;fpd; kl;L Y=20x109Nm-2 , Vfgupkhz tpupifj;jpwd; 12x10-5K -1 MFk;.

(1) 1.2x 106 Nm-2 (2) 2.4 x 106 Nm-2 (3) 7 x 106 Nm-2 (4) 7.2 x 106 Nm-2 (5) 7.2 x 109 Nm-2

(2019/New&Old/23)

(5) rJu tbt mbiaf; nfhz;l jhq;fp xd;wpDs; 20cm cauj;jpw;F ePHepug;gg;gl;Ls;sJ. 1500Nm-1 tpir khwpyp cila tpw;RUs; xd;Wld;,izf;fg;gl;Ls;s xU Kryj;ijg; gad;gLj;jp jhq;fpahdJ glj;jpy;fhl;lg;gl;lthW ,uz;L rk ghjpfshfg; gpupf;fg;gLfpwJ. tpw;RUspd;neUf;fy; (ePupd; mlHj;jp 1000kgm-3 Kryj;jpw;Fk; jhq;fpf;Fk; ,ilapy;cuha;T ,y;iy vdf; nfhs;f)(1) 1cm (2) 1.1cm (3) 1.2cm

(4) 1.3cm (5) 1.5cm

(2018/22)

(6) ,ay;Gepiy ePsk; l1 ck; tpir khwpyp K1 ck; nfhz;l tpw;RUs; xd;W ,ay;G epiy ePsk; l2ck; tpirkhwpyp K2 ck; nfhz;l ,d;ndhU tpw;RUSld; rkhe;jukhf ,izf;fg;gl;Lcs;sij cU fhl;Lfpd;wJ.

,U RUs;fspdJk; NrHf;ifahdJ ,ay;G epiy ePsk; l ck; tpir khwpyp K ck; nfhz;l jdp xU tpw;RUisg; Nghd;W njhopw;gLfpwJ

(2018/42)

(7) X,Y vd;gd xNu gjhu;j;jj;jpdhyhd rk FWf;F ntl;Lg;gug;Gs;s ,U ,iofs; MFk;. Mdhy;X vd;Dk; ,ioapd; ePsj;jpYk; Y vd;Dk; ,ioapd; ePsk; rpwpjsT FiwthdJ. ,U,iofspdJk; RahjPd Kbtplq;fspy; xd;W $iuAld; xUkpf;f ,izf;fg;gl;L kW RahjPdKbtplq;fs; xd;whf ,Uf;FkhW gpbf;fg;gLfpwJ. (,e;epiyapy; X ,d; ,OtpirGwf;fzpf;fj;jf;fJ. Y ,w;F Fwpj;j ,Otpir cz;L.) ,k;Kidapy; Nrh;j;jp ,iof;fhd,Oit gbg;gbahf mjpfupf;fg;gbd; X,Y ,iofspYs;s ,Oit vq;qdk; ele;J nfhs;Sk;vd;gij gz;gwp Kiwahf tpsf;FtJ gpd;tUtdtw;Ws;

(1) X Kjypy; tpfpjrk vy;iyia milAk;. ,jd; gpd;dh; tpirapd; ngUk;gFjp Y ,y;njhopw;gLk;.

(2) Y Kjypy; tpfpjrk vy;iyia milAk;. ,jd; gpd;dh; tpirapd; ngUk;gFjp X ,y;njhopw;gLk;.

(3) X Kjypy; tpfpjrk vy;iyia milAk;. ,jd; gpd;dh; tpirapd; ngUk;gFjp X ,y;njhopw;gLk;

(4) Y Kjypy; tpfpjrk vy;iyia milAk;. ,jd; gpd;dh; tpirapd; ngUk;gFjp Y ,y;njhopw;gLk;.

(5) X Kjypy; tpfpjrk vy;iyia milAk;. ,jd; gpd;dh; gpuNahfpf;fg ;gL;k; tpir ,U,iofspw;Fk; rkkhfg;gq;fplg;gLk;

(2017/20)

(8) cNyhff; fk;gpfs; kPjhd jifg;G tpfhugupNrhjidfspy; jifg;G mr;R 108 Pa

myFfspYk; tpfhu mr;R tPjj;jpYk; (%)Fwpf;fg;gl;Ls;sJ Fwpj;j fk;gp xd;wpw;fhdtiuG fPNo fhl;lg;gl;Ls;sJ. fk;gpapd;gjhHj;j;jpw;fhd aq;fpd; kl;bd; ngWkhdk;.

(1) 6.0 x107 Pa (2) 7.5 x108 Pa (3) 1.5 x109 Pa (4) 6.0 x109 Pa (5) 6.0 x1010Pa

(2016/43)

(9) A,B vDk; ,U cUistbtf; Nfhy;fspy; A apd; ePsk; B apd; ePsj;jpd; %d;W klq;fhfTk; Aapd; Miu B apd; Miuapd; ,U klq;fhfTk;. B apd; aq;fpd;kl;L A apd; aq;fpd; kl;bd;%d;W klq;fhffTk; ,Ug;gpd; ,U Nfhy;fSf;Fk; F vDk; ,Otpir gpuNahfpf;fg;gl A apy;Vw;gLk; ePl;rp Δl vdpd; B apy; Vw;gLk; ePl;rp

(2015/10)

Nkw;gug;gpOtpir

(10) kaph;j;Jisf;Fohapd; xUKidapy; rth;fhug; glyk; ,lg;gl;L kWKidahdJ Foha; epiyf;Fj;jhf ,Uf;Fk; tifapy; ePhpDs; mkpo;j;jg;gLfpd;wJ. ,t;thW mkpo;j;jg;gl Fohapd;Nky;Kidapy; rth;f;fhuf;Fkpo; cUthfpd;wJ cUthFk; rth;fhuf;Fkpopd; MiuahdJgpd;TUtdtw;upy; vjpy; jq;fpapuhJ.

(1) ePhpd; Nkw;gug;gpOtpirapy;;(2) rth;fhuglyj;jpd; Nkw;gug;gpOtpirapy;;(3) Fohapd; ePsj;jpYk; mkpo;j;jg;gl;l Fohapd; Moj;jpYk;(4) ePhpd; mlh;j;jpapy;(5) tspkz;ly mKf;fj;jpy;

(2019/New&Old/31)

(11) rtHf;fhu glyj;jpd; gUkid 10cm x6cm ,ypUe;J 10cm x11cm Mf mjpfupg;gjw;F nra;ag;gLk;Ntiy 3x10-4J Mapd; rtHf;fhuj;jpd; Nkw;gug;gpOtpir ahJ?

(1) 1.5 x10-2Nm-1

(2) 3.0 x10-3Nm-1

(3) 6.0 x10-2 Nm-1

(4) 11.0 x 10-2Nm-1

(5) 3.0 x10-2Nm-1

(2018/16)

(12) fhl;bathW T ntg;gepiyapYs;s tspapy; fhzg;gLk; Nkw;gug;gpOtpirAilarth;fhufiurypdhyhd r MiuAila rtHf;fhuFkpo; gw;wpa gpd;tUk; $w;WfSs; gpioahdJ

(1) fhl;ba rtHf;fhuFkpopDs; cs;s tspapd; myFfdtstpw;fhd %y;tspkz;lytspapYk;> (4/rRT) ,dhw; $lthFk;.

(2) ntg;gepiy rpwpjsthy; mjpfupf;f Fkpo; vg;NghJk; ngUf;ff; fhzg;gLk;.(3) ntg;gepiy rpwpjsthy; mjpfupf;f FkpopDs; mKf;fk; mjpfupf;Fk;.(4) ntg;gepiy rpwpjsthy; mjpfupf;f FkpopDs; cs;s thAthy; Ntiy nra;ag;gLk;.(5) ntg;gepiy mjpfupg;gpd; NghJ rtHf;fhuf;Fkpo; ngWk; ntg;gk; MdJ thAtpdhw;

nra;ag;gLk; Ntiy> thAtpd; cl;rf;jp mjpfupg;G> Fkpo; Mf;fg;gl;l rth;f;fhuf;fiurypd;ntg;gepiy mjpfupf;f Njitahd ntg;gk; vd;gtw;wpd; $l;Lj;njhiff;Fr; rkd;

(2018/43) (13) Nfhstbt fz;zhbf;FLitapDs; mjDld; 600 njhLiff;NfhzKila jputk; xd;W

cs;sij fhl;Ltjpy; rupahdJ

(2016/04)

Unit 1O Mechanical Properties of Matter

Q Ans Q Ans Q Ans Q Ans Q Ans Q Ans Q Ans Q Ans Q Ans

(1) 4 (2) 4 (3) 4 (4) 5 (5) 4 (6) 2 (7) 2 (8) 4 (9) 2

(10) 5 (11) 5 (12) 3 (13) 2

Mechanical Properties of Matter

01.jputk;; xdwpd; gug;gpOitiaj; Jzptj;w;fhd ghpNrhjid xOq;fikg;G xd;;iw thpg;glk; fhl;;Lfpd;wJ. jputj;jpd; gug;gpOit Tck; mlu;j;jp 2 ck;

nkypkhdpapy; ,lg;gl;Ls;s kz;nzz;nza;apd; mlu;;j;jp 1 ck; cgfuzj;jpd; kapu;j;Jisf;Fohapd; mftpl;;lk; d ck; nkypkhdpapd; jput epuy;fSf;F ,ilapyhd cauq;fspd; cr;r tpj;jpahrk; h2 ck; jput

kl;lj;jpypUe;J kapu;j;Jisf; Fohapd; me;jk; tiuapyhd Mok; h1 ck;

tspkz;ly mKf;fk; ck; MFk;.

(a)kaphj;Jisf; Fohapd; jputj;jp;y; mkpo;e;Js;s me;jj;jpy; tspf;Fkpopnahd;W cUthfp> nkJthf tspf;Fkpopahf ntspNaWk; re;ju;g;gj;jpy; Fkpopf;Fs; mKf;fk; P1 ,w;fhd Nfhitia NkNy jug;gl;l fzpaq;fs; rhh;ghf jUf.

……………………………………………………………………………………………

……………………………………………………………………………………………

(b)jputj;jpy; Fkpopf;F ntspNa cs;s mKf;fk; P2 ,w;fhd Nfhitia NkNy jug;gl;l fzpaq;fs; rhh;ghf jUf.

………………………………………………………………………….…………………

………….………….………………………………………………………………………

(c)Fkpopf;F FWf;Nfahd kpifmKf;;fj;jpw;fhd Nfhitia T, d Mfpad rhh;ghf vOJf.

…………………………………………………………………………………………………………

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(d)(i) T, d,P2,P1 Mfpatw;Wffpilapyhd njhlh;G ahJ?

……………………………………………………………………………………………………………

……………………………………………………………………………………………………… .

(ii) T ,w;fhd Nfhitia d, h1, h

2 1,

2 Mfpad rhh;ghf ngWf.

………………………………………………………………………………………………………

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(e) ePh; gad;gLj;;Jtjw;Fg; gpd;tUk; msf;Fk; cgfuzq;fs; ck;kplk; jug;gl;;Ls;sd:

Xh; miukPw;wh;f;Nfhy;> xU Ntzpah;,Lf;fp> xU efUk;EZf;Ff;fhl;b jug;gl;Ls;s cgfuzq;fspy; h1 , h2 , d Mfpatw;iw msg;gjw;F kpfTk;

cfe;j cgfuzk; ahJ? …………………………………………………………………………………………

(f) kaph;j;Jisf;Fohapd; rPuw;wjd;ik ghpNrhjid KbTfisg; ghjpf;Fkh? tpsf;Ff. .............................................................................. .......................................................................................................................................................................................................................................... ...................... ........................................

(g) 4 10-4 m tpl;lj;ijf; nfhz;l kapu;j;Jisf;FohapYs;s tspapdJ mKf;fkhdJ mjpfupf;fg;gl;L nkypkhdpnahd;iwg; ghtpj;J msf;fg;gl;lJ. ,t;tKf;f mjpfupg;gpd; tpisthf Fohapd; fPo;Kidapy; tspf; Fkpopnahd;W Njhd;wpaJ.,f;Fkpop cila

KidAk; NghJ nkypkhdpapd; jputkl;lq;fspd; tpj;jpahrk; 9 10-2 Mff;fhzg;gl;lJ.

,k;kapu;j;Jisf; Fohapd; fPo;Kid jputkl;lj;jpd; fPo; 2.5 10-2m Moj;jpy; fhzg;gl;lJ. KfitapYs;s jputj;jpdJk; nkypkhdpj;jputj;jpdJk;;; mlu;;;; ;;;;;;;;;;;;;;;;;;;;;;;j;jpfs; KiwNa 800

kg m-3> 900 kg m-3 MftpUg;gpd; KfitapYs;s jputj;jpd; Nkw;gug;G ,Oitia fzpf;f

………………………………………………………………………………………… ..…………………

………………………………………………………………………………………… ...................................

(h) jputq;fspy; Nehf;fg;gLk; gug;G ,Oitj; Njhw;wg;ghl;Lf;Fhpa mbg;gilf; fhuzk; ahJ?

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(2015/structure)

02.

(a) ngUk;ghyhd jputpaq;fspd; jifg;G tpfhu tisap fPNo fhl;bathW fhzg;gLk;. ,t; tisapapy; 𝐴,𝐵 Mfpa Gs;spfis ,dq;fhz;f.

(b) (1) 𝑙 ePsKs;s 𝐴 FWf;Fntl;Lg;gug;Gila epiyf;Fj;Jf;fk;gpapy; RahjPdkhf 𝑚 jpzpT njhq;ftplg;gl;l NghJ 𝑒 J}uk; ePl;rp mile;jjhapd; mf; fk;gpj; jputpaj;jpd; aq;fpd; kl;Lf;fhd Nfhitia jug;gl;l gukhzq;fs; rhu;gpy; jUf.

…………………………………………………………………………………………………………..…………………………………………………………………………………………………………..…………………………………………………………………………………………………

(2) tpdh (b) (1) ,y; ePu; vOjpa Nfhit typjhtjw;fhd epge;jidiaj; jUf. ………………………………………………………………………………………………………….. (c) cUis tbtf; fk;gp xd;wpd; aq;fpd;kl;il Jzptjw;F tof;fkhf gad;gLj;jg;gLk; gupNrhjid mikg;ig mUfpYs;s cU fhl;Lfpd;wJ.

gupNrhjidf; fk;gpapy; ntt;NtW Nkyjpf epiwf;F(𝑁) xj;j Nkyjpf ePl;rpahdJ (𝑒) mwpag;gl;L tiuag;gl;l tiughdJ fPNo jug;gl;Ls;sJ.

(1) tiugpd; gbj;jpwidf; fhz;f? ……………………………………………………………………………………………………….….………………………………………………………………………………………………….........…… …………………………………………………………………………………………………………..

(2) gupNrhjidf; fk;gpapd; FWf;F ntl;Lg; gug;ig mwptjw;F ePu; msf;f Ntz;ba mstPL ahJ? mjw;F gad;gLj;jf;$ba mstPl;Lf; fUtp ahJ? …………………………………………………………………………………………..………………..……………………………………………………………………………………….......……………..…

(3) gupNrhjidf; fk;gpapd; FWf;F ntl;Lg;gug;G 1 X10−6𝑚2 vdTk; fk;gpapd; ePsk; 2𝑚 vdTk; jug;gl;bUg;gpd; fk;gpapd; aq;fpd; kl;il Jzpf. …………………………………………………………………………………………………………..………………………………………………………………………………………………....……...……………………………………………………………………………………………………………..…………………………………………………………………………………………………….......… (4) ,q;F gupNrhjidf; fk;gp> khl;Nlw;Wf; fk;gp Mfpa ,U fk;gpfs; gad;gLj;jg;gLtjw;fhd fhuzq;fs; ,uz;bid $Wf.

1. ……………………………………………………………………...………………………………… 2. ………………………………………………………………………………...………………………

(5) ,g; gupNrhjidapy; gupNrhjidf; fk;gp tpfpjrk vy;iyia jhz;ltpy;iy vd;gij vt;thW cWjpg;gLj;JtPu;? ……………………………………………………………………………………………………………

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(6) tiugpYs;s P, Q Mo;$Wfs; kw;iwa Mo;$WfspypUe;J NtWgl;Lf; fhzg;gLtjw;fhd fhuzkhf mikaf;$baJ. …………………………………………………………………………………………………………..

$wg;gl;l A apypUe;J B tiu, B apypUe;J C tiu, C apypUe;J A tiu ,af;fj;jpy; efh;j;jpf;fk;gp mwf;$ba re;jh;gg;k;

…………………………………………………………………………………………………………..

(a)

i. GtNrapd; rkd;ghl;il tof;fkhd FwpaPLfSld; $Wf. ii. fpilf; FohapD}L 𝑄 fdtsTg; gha;r;ry; tjPj;jpy; jputnkhd;W ghAk; NghJ Fohapd; KidfSf;F ,ilapyhd mKf;f tpj;jpahrk; ∆𝑃 vdpd; tpuakhFk; tY 𝑝 MdJ 𝑝 = ∆𝑃𝑄 ,dhy; jug;gLk;. ,J gupkhzg;gb rupahdJ vdf; fhl;Lf. iii. NkNy tpdhf;fspy; $wg;gl;l ,U njhlu;GfspYk; ,Ue;Jk; Fwpj;j FohapD}L jputk; ghAk; NghJ tpuakhFk; tY mjD}lhd fdtsT gha;r;ry; tPjk; 𝑄 ,d; ,uz;lhk; tYTf;F Neu;tpfpjrkd; vdf; fhl;Lf. (𝑝 ∝ 𝑄2)

(b) rpwpa efunkhd;wpd; ePu;toq;fy; njhFjpapy; Kjypy; ePu; Kjy; xd;wpypUe;J ePuhdJ

Rj;jpfupf;fg;gl;L gpd; efu ePu;toq;fy; njhFjpf;F ePuhdJ FohapD}L (Foha; 𝐴𝐵 ) tpepNahfpf;fg;gLk;. gpd; efu ePu;toq;fy; ikaj;jpypUe;J efuj;jpDs;Ns ePu; tpepNahfpf;fg;gLk;. Foha; 𝐴𝐵 ,d; cs ;Miu 20𝑐𝑚 MfTk; mjd; ePsk; 100𝑘𝑚

MfTk; Kid 𝐵 apy; 1.5 × 105𝑃𝑎 mKf;fk; vg;NghJk; Ngzg;gl Ntz;Lk;. 𝐵𝐶= 20𝑘𝑚 vdf; nfhs;f.

(c) efupd; ruhrup ntg;gepiy 20𝑂𝐶 ,y; ePupd; gpRf;Fikf; Fzfk; × 1 × 10−3𝑃𝑎𝑠 vdTk; 𝜋 = 3 vdTk;; nfhs;f. fPo;tUk; ml;ltizahdJ Fwpj;j efuj;jpd; xU ehspw;fhd ePu;g; gad;ghl;il fhl;Lfpd;wJ.

XU tpisahl;bw;fhf mikf;fg;gl;Ls;s njhFjp mUfpy; fhl;lg;gl;Ls;sJ. ,q;F Jhzpd; kPJ eOtpr;nry;yf;$bathW JhZld; ,izf;fg;gl;l tpisahl;Ldiuf; nfhz;l njhFjpia efu;j;jpf;fk;gpapd; cjtpAld; Nky;fPohf Nkhl;lhh; njhFjp; efu;j;Jfpd;wJ A apypUe;J B tiu rpwpa

khwhNtfj;JlDk; gpd; B apypUe;J C tiu

GtpaPh;gg;pd;fPo; ,af;fkhfTk; ,Wjpahf C apypUe;J

A tiu mkh;KLfypaf;fj;JlDk; ,af;fp A apy; Xa;tilar;nra;fpd;wJ.

(2019 str new/old)

03.

i. neupryhd fhyg;gFjpapy; Foha; 𝐴𝐵 ,w;F FWf;Nf Ngzg;gl Ntz;ba mKf;f

tpj;jpahrj;ijf; fhz;f. ii. neupryhd fhyg;gFjpapy; Fohapd; gFjp 𝐶 ,Ny css; mKf;fj;ij fhz;f. iii.

neupryw;w fhyg;gFjpapy; Foha; 𝐴𝐵 ,w;F FWf;Nf Ngzg;gl Ntz;ba mKf;f tpj;jpahrj;ijf; fhz;f.

iii. neupryhd fhyg;gFjpapYk; neupryw;w fhyg;gFjpapYk; ghFik tpirfshy; tpuakhFk; tYf;fSf;fpilapyhd tpfpjj;ijf; fhz;f.

iv. ePu;r; Rj;jpfupg;G epiyak; rupahd Kiwapy; ePupd; td;ikia mfw;whjjhy; Fohapd; Miu 10% ,dhy; Fiwtile;jjhf mwpag;gl;lJ. ,jdhy; ePu;g;gha;r;riy khwhJ Ngz gpuNahfpf;;f Ntz;ba mKf;f tpj;jpahrk; vj;jid klq;fhf mjpfupf;f Ntz;Lk;; vdf; fhz;f.

(c)ePiu neupryhd fhyg;gFjpapy; toq;Ftjw;F mjpf tYTila gk;gpfs; Njitg;gLtJld; ePu; toq;fYf;fhd nryTk; mjpfkhf css; J. Nkw;gb gpur;rpidfis Fiwg;gjw;fhf ePu; toq;fy; njhFjpapy; ePu;j; jhq;fpfs; (water towers) gad;gLj;jg;gLfpd;wd. ,q;F 𝐶 apy; ePu;j;jhq;fp mikf;fg;gl;Ls;sjhf nfhs;f. neupryw;w fhyg;gFjpapy; ePu;j; jhq;fpapy; ePuhdJ epug;gg;gLk; mNjNtis neupryhd fhyg;gFjpapy; gk;gpfspd; nraw;ghL epWj;jg;gl;L jhq;fpapypUe;J ePu; toq;fy; Nkw;nfhs;sg;gLk;.

i. ePu;j; jhq;fpahdJ efupd; xU ehs; ePu;j;Njitf;fhd ePupd; msit nfhz;bUf;f Ntz;Lnkdpd; ePu;j; jhq;fpapd; nfhs;sitf;fhz;f.

ii. neupryhd fhyg;gFjpapy; NkNy(b) ,y; $wpa tPjj;jpy; C ,ypUe;J B tiu ePu; tpepNahfj;ij Nkw;nfhs;tjw;F Njitahd mKf;f tpj;jpahrj;ij toq;f ePu;j;jhq;fp jiuapypUe;J mika Ntz;ba kpff; Fiwe;j cauk; ahJ? ePupd; mlu;j;jp 1000𝑘𝑔𝑚−3 vd vLf;f.

iii. njhlu;r;rpahd ePu;toq;fypd; gpd; ePu;j;jhq;fpapd; css; ePupd; msT 2𝑚 ,dhy; Fiwtile;Js;sJ. ,jdhy; ePu; toq;fy; tjPj;jpy; Vw;gl;l rjtjPf; Fiwitf; fhz;f.

(d)

Nkw;Fwpj;j Njitf;fhf 20 cm MiuAila Foha;f;F gjpyhf mNj nkhj;j FWf;Fntl;Lg;gug;G ngwg;gLk; tpjkhf ,U Foha;fs; rkhe;jukhf ,izf;fg;gLnkdpd; ePu; NkNy b(i) ,y; fzpj;j mKf;f tpj;jpahrk; mjpfupf;Fkh my;yJ FiwAkh vdf; Fwpg;gpLf.

04. jput%yf;$Wfs; ,uz;bw;fpilapyhd gpizg;ig cilf;fj; Njitahd rf;jp mtw;wpd; gpidg;G rf;jp (E0) vdg;gLfpwJ. ,r;rf;jp mt;tpU %yf;$WfisAk; jdpikg;gLj;jg;gad;gLfpwJ. mjhtJ mtw;wpw ;fpilapyhd mOj;jrf;jpiag; g+r;rpakhf;FfpwJ. xU jputj;jpDs; cs;s xt;nthU %yf;$Wk; n vz;zpf;ifahd mLj;Js;s may; %yf;$Wfshy; #og;gl;bUf;Fk;. MfNt jputj;jpDs; cs;s %yf;$W xd;iw mjd; mLj;Js;s %yf;$Wfspd; gpizg;gpy; ,Ue;J cilg;gjw;Fj; Njitahd rf;jp nE0

(2019 ess new/old)

jput Nkw;gug;G xd;W Gjpjhf cUthf;fg;gLk; NghJ jputj;jpd; cs;spUe;J Nkw;gug;gpw;F tUk; %yf;$iwf;fUjpd; mit n/2 vz;zpf;ifahd %yf;$Wfspd; gpizg;gpy; ,Ue;J tpLtpf;fg;gl;litahf ,Uf;Fk; (glj;ijg; ghHf;f). MfNt ,jd; NghJ xU %yf;$wpw;F toq;fg;gLk; rf;jp ½nE0. Gjpa Nkw;gug;G N vz;zpf;ifahd %yf;$Wfis XuyF gug;gpy; nfhz;bUg;gpd; mq;F N/2 vz;zpf;ifahd Nrhb %yf;$Wfs; fhzg;gLk;. MfNt XuyF gug;Gila Gjpa Nkw;gug;G xd;iw cUthf;fj; Njitahd rf;jp.

T = ½ N x ½ nE0 = ¼ NnE0

,t;thW Nkw;gug;G xd;wpd; cUthf;fj;jpw;F toq;fg;gLk; rf;jpNa mk;Nkw;gug;gpd; Nkw;gug;G rf;jp vdg;gLk;. ntg;gepiy khwhJs;sNghJ jputk; xd;wpd; Nkw;gug;ig Xuyfpdhy; mjpfupg;gjw;Fj; Njitahd rf;jp mj;jputj;jpd; Nkw;gug;G ,Otpir vdg;gLk;. jputNkw;gug;G xd;iw khwh ntg;gepiyapy; mjpfupf;fr; nra;jy; XH rkntg;gr; nray;Kiw MFk;

i. %yf;$Wfspw;fpilapyhd gpizg;G rf;jp vd;why; vd;d? ii. gpizg;Grf;jp E0 Mf cs;s ,U %yf;$Wfspd; mOj;j rf;jp ahJ? iii. jputj;jpDs; cs;s %yf;$W jputNkw;gug;gpw;F tUk; NghJ vj;jid %yf;$Wfspd; gpizg;gpypUe;J tpLtpf;fg;gLfpd;wJ vd;gij mJ jputj;jpDs; cs;s NghJ may; %yf;$Wfspd; vz;zpf;ifapy; jUf. iv. NkYs;s juTfspypUe;J A Nkw;gug;gsTs;s jput Nkw;gug;gpd; Nkw;gug;G rf;jp ahJ? (b) jputq;fs; nfhjpj;J Mtpahjypd; NghJ jputq;fspDs; cs;s %yf;$Wfspd; gpizg;G cilf;fg;gLfpwJ. ,t;thW L %yf;$Wfs; ciltjw;Fj ; Njitahd rf;jp ½LnE0 1kg ePH nfhjpj;J MtpahFk; nraw;ghl;bd; NghJ ePH %yf;$W Mtp%yf;$whf cilf;fg;gLtjw;F 2.3 x 106 J rf;jp Njitg;gLfpwJ. xU %y; ePH %yf;$Wfspd; jpzpT 0.018Kg. mtfhjNuh vz;;; ; 6 x1023mol-1 ePupw;F n =10 Mapd; ePH%yf;$Wfspw;fpilapyhd gpizg;Grf;jpiaf; fhz;f. ePupd; myF Nkw;gug;gpy; cs;s %yf;$Wfspd; vz;zpf;if N = 2x1018m- 2 MfTk;> Fwpj;j ntg;gepiyapy; ePH %yf;$Wfspd; gpizg;G cilTf;fhd rf;jp tpdh (b)(i) ,y; fzpf;fg gl;l rf;jpf;F rkd; vdTk; nfhz;L Nkw;gug;gpOitapd; tiutpyf;fzj;jpw;fikthf ePupd; Nkw;gug;G ,Oitiaf; fzpf;f rpy rpwpa g+r;rpfs; ePupd; gug;gpOit fhuzkhf ePHg;gug;igf; fPNo js;spf;nfhz;L ePHg;gug;Gfspy; ele;J nry;yj;jf;fd g+r;rpfspd; mbfs; mz;zsthff; Nfhskhditahff; fUjg;glyhk;. ,t;thwhd 6 fhy;fisf ; nfhz;l xU g+r;rpapd; fhy; xd;wpd; jput Nkw;gug;gpy; njhLifAWk; tl;lf;FWf;Fntl;bd; Miu 3x10-5m Mapd; Nkw;Fwpg;gpl;l ePupy; mJ cs;s NghJ ghjj;ij njhLk; jputNkw;gug;G epiyf;Fj;jhf mikf;Fk ; Nfhzk; θ MFk;. Cosθ = 0.8 Mapd; g+r;rpapd; jpzpit kg ,y; jUf. (π = 0.3 vd;f) NkNy $wg;gl;l g+r;rp NtNwhH jputj;jpy; tplg;gLfpd;wJ. mj;jputk; ePupd; Nkw;gug;gpOitapYk; $ba Nkw;gug;gpOitia nfhz;Ls;s NghJk; ,j;jputj;jpy; g+r;rp mkpo;tjhf fhzg;gLfpwJ. ,jw;fhd fhuzk; ahJ?

(2017/essay)

05.(a) xU ghj;jpuj;jpd; mbapy; r MiuAila xU rpwpa Jthuk; xd;W cs;;;sJ. ghj;jpuj;jpDs; xU jputk; nkJthf Cw;wg;gLfpd;wJ. jput Mok; h cld; jput Fkpopd; tsh;r;rpapd; cUf;fis tiue;J fhl;Lf. ,jpypUe;J Jthuj;jpD}L jputk; ntspNawj; njhlq;Fk; NghJ h ,w;F jputj;jpd; mlh;j;jp Nkw;gug;gpOtpir T, Jthuj;jpd; Miu r rhh;ghf xU Nfhitapid ngWf.

(b) X MdJ xU jpwe;j cUis ahFk;. xU ghukw;w mb PQ

MdJ k kPspay; ,ioapd; ,Oitapdhy; glj;jpy; fhl;ba epiyapy; cs;sJ. cUisAk;;> mbAk; nghUe;Jk; ,lj;jpD}L jputk; ntspNawtpy;iy vdf; nfhs;f.AB MdJ 1mm MiuiaAk; 44 cm ePsj;jpidAk; nfhz;l xU rPuhd Foha; MFk;. H cm mKf;fj;jpy; xU gpRf;Fj;jputk; Nkw;Fwpg;gpl;l cUisg;ghj;jpuj;jpy; Nrkpf;fg;gLfpd;wJ.

i) 1 mm MiuAila xU rpwpa Jthuk; PQ ,y; cs sJ. jputj jpd

mlh;jjpAk mjd Nkw;guggpOitAk KiwNa 103kg m-3 ck> 0.5 N m-1 ck MFk. jputk JthujjpD}L ntwpNawjnjhlqFk jWthapy h ,idf fzpff.

(ii) (a) AB apD}L nryYk jputjjpw;F> xU nrf;fdpy; nry;Yk; jputj;jpd; fdtsT Q vdpd; Q ,w;F GtNrapd; rkd;ghl;bid vOJf.

(b) jputj;;jpd; gpRf;Fik 2x10-2 Pa s ck;> H = 70 cm ck; Mapd; jputk; cUisapDs; tpoj; njhlq;fpa Neuk; njhlf;fk; Jthuj;jpD}L jputk; ntspNawj; njhlq;Fk; Neuk; tiu vLj;j Neuj;jpidf; fhz;f.

mb PQ ,dJ gug;;gsT 10-5 m2 MFk.

(iii) ,wg;gh; gl;bapd; ,aw;if ePsk;; 1 m ck;> mjd;

FWf;Fntl;Lg;gug;gsT 10-6 m2 ck; MFk;. Jthuj;jpD}L jputk; ntspNaWKd; jl;L PQ tpw;Fk; > cUisf;Fk; ,ilNa jputk; ntspNawhky; ,Ug;gjw;F Muk;gj;jpy; gl;bf;F nfhLf;fNtz;ba ePlrpiaf fhz;f. (,wg;ghpd;

aq;fpd; kl;L 5 x106 Pa)

(2015/essay)

06. cUis tbtpyhd jpwe;j ghj;jpuk; xd;W ghFepiy cila jputj;jpidf; nfhz;Ls;sJ. cUf;fpdhyhd rpwpa Nfhsk; xd;W Gs;sp X ,ypUe;J Xa;tpypUe;J ,aq;ftplg;gLfpd;wJ. Gss;p X ,w;Fk; jputNkwg;ugg;pwF;k ;,ilapyhd J}uk; 0.8 cm MFk;.

(i) Nfhsk; jputNkw;gug;ig mila vLf;Fk; Neuj;ij fhz;f.

(ii) NfhskhdJ jputNkw;gug;ig milAk;NghJ mjd; Ntfj;jpidf; fhz;f.

(iii) Nkw;Fwpg;gplg;gLk; NfhskhdJ ghFepiyj; jputj;jpDs; ,aq;Fk;NghJ mJ milAk; KbTNtfj;jpidf; fhz;f. jputj;jpd; mlu;j;jp 1000 kgm-3 ,

ghFepiyf; Fzfk; 5 ×10-2 Nm-2 s-1.

Nfhsj;jpd; Miu 1 mm, Nfhsj;jpd; mlu;j;jp 10000 kgm-3 vdf; nfhs;f.

(iv) tpdh (ii) ,y; NfhskhdJ rf;jp ,og;G ,d;wp kpf tpiuthf jputj;jpDs; GFkhapd; ,jd; Ntfk; Neuj;Jld; khWk; tpjj;jpid tiugpy; tiue;J fhl;Lf.

(v) Gs;sp X ,Yk; rw;W cauj;jpy; ,Ue;J cUf;Ff; Nfhsk; ,aq;f tplgg;Lkhapd; Muk;gj;jpypUe;J ,jd; Ntfk; Neuj;Jld; khWk; tpjjj;pid tiugpy; fhl;Lf. (jput Nkwg;gpy; GFk;NghJ Vwg;Lk; rf;jp ,og;Gf;fis Gwf;fzpf;f)

(2016/essay)

07.(a) nurpypd; (Resilin) vd;gJ mrhjhuzkhd kPspay; ,ay;Gfisf; fhl;lj;jf;f xH GujkhFk;. ,J rpytifg;g+r;rpfspw; fhzg;gLfpwJ. nurpypdpd; jifg;G tpfhu tisap fPNo jug;gl;Ls;sJ. ,t; tisap ,Oit> neUf;fy; Mfpa ,U re;jHg;gq;fspw;Fk; Vw;GilaJ.

i. Gs;spfs; A,B I ,dq;fhz;f?

ii. nurpypdpd; aq;fpd;kl;ilf; fzpf;f?

(b) g+r;rp xd;wpy; mjd; rpwFfSld; nurpypd; mjd; clypw;F ,izf;fg;gl;Ls;sJ. ,g;g+r;rp rpwfbf;Fk; NghJ rpwFfs; NkNy nry;ifapy; nurpypid tpfhukiltJld; rpwFfs; fPNo tUk; NghJ nurpypd; jsHthf cs;sJ. xU rpwFld; ,ize;Js;s nurpypid jsHthf

cs;s NghJ 1cm ePsk;> 1mm2 FWf;Fntl;Lg;gug;igf; nfhz;lJ. xU g+r;rp ,U rpwFfisf; nfhz;bUf;Fk;. g+r;rp rpwfbf;Fk; NghJ nurpypdpy; Vw;gLk; tpfhuk; 3 MFk;. ,jd; NghJ rpwF NkNy nry;ifapy; ngw;Wf;nfhs;Sk; kPspay; mOj;j rf;jpia rpwF fNPo tUk;NghJ ntsptpLk.; ,r;rf;jpapd; 96% g+r;rpahy; Ntiy nra;tjw;fhf ngw;Wnfhs;sg;gLk;.

i. nurpypd; 3 vDk; tpfhukile;Js;s NghJ mjpy;jhf;Fk; tpiria fzpf;f.

ii. ,jd; NghJ xU rpwFld; ,ize;Js;s nurpypdpy; Nrkpf;fg;gLk; rf;jp ahJ? g+r;rp xd;W me;juj;jpy; epw;gijf;fUJf. ,jw;fhfg; g+r;rp 1s ,w;F 5 jlitfs; vDk; tPjj;jpy; rpwfbf;f Ntz;bAs;sJ. ,r;re;jHg;gj;jpy; g+r;rpahy; nra;ag;gLk; Ntiy <Hg;G tpirf;nfjpuhdjhFk;.

iii. me;juj;jpy; epw;Fk; NghJ g+r;rpahy; Ntiy nra;ag;gLk; tPjk; (tY) ahJ?

g+r;rp xd;W khwh Ntfj;Jld; fpilahfg; gwg;gij fUJf. ,g;gwj;jypd; NghJ NgZ}ypapd; tpisTfhuzkhf mjdhy; <Hg;Gtpirf;F vjpuhf nra;a Ntz;ba Ntiyapd; msT Fiwthf fhzg;gLk;. vt;khwhNtfj;jpy; g+r;rpahdJ fpilahfg; gwf;ifapYk; 0.064W vDk; tY <Hg;Gtpirf;nfjpuhf Ntiy nra;ag;NghJkhdjhFk;. vdpDk; ,q;F kV vDk; tspj;jil tpir ,Ug;gjhy; g+r;rp mjw;nfjpuhf Ntiy nra;a Ntz;bAs;sJ.

iv. g+r;rp 20cms-1 vDk; khwh Ntfj;jpy; gwf;Fk; NghJk; xU nrf;fdpw;F 5 jlitfs; tPjj;jpNyNa rpwfbf;fpwjhapd; k ,d; ngWkjp ahJ?

v. g+r;rpahy; xU nrf;fdpw;F mjpfgl;rkhf 10 rpwfbg;Gf;fis epfo;j;j KbAkhapd; g+r;rpahy; fpilahf gwf;fj;jf;f caH Ntfk; ahJ?

(c) njs;Sg;g+r;rp (flea) MdJ mjd; ,U gpd;dq;fhy;fspYk; cs;s (coxa) vDk; gFjpapy; nurpypdhyhd jpz;Lfis (pad) nfhz;bUf;Fk; mj;jpz;Lfs; 2x10-4m gf;fePsKila rJuKfpahf fUjyhk; ,g;g+r;rp rpwFfisf; nfhz;bUg;gjpy;iy. nurpypdpd; cjtpAld; Js;sp NknyOjNy mjd; ,lk;ngaHjy; cj;jpahFk;. glj;jpy; fhl;bathW nurpypd; jpz;Lfs; tpw;RUs; Nghyr; nraw;gl;L RUq;Ftjhy; ngwg;gLk; kPs;jd;ik rf;jpia 92% jpwDld; ,af;frf;jpahfg; ngw;W NknyOe;J vwpag;ghijapy; ,aq;FfpwJ. njs;Sg;g+r;rpapd; jpzpT 0.46mg MFk;. njs;Sg;g+r;rp mnrsfupakpd;wp milaj;jf;f caH neUf;fy; tpfhuk; 0.5 MFk;.

i. nurpypd; jpz;L xd;wpd; tpirkhwpyp k If; fzpf;f?

ii. tpfhuk; 0.5 MfTs;s NghJ njs;Sg;g+r;rpapd; nurpypd; jpz;L xd;wpw;fhf;Fk; tpiria fzpf;f?

iii. njs;Sg;g+r;rp ngwj;jf;f caH Ntfk; ahJ?

(2018/essay)