Tiêu đề 8. P2C8 (Beginning of Modern Physics)_With Solve_Ridoy15.12.24.pdf ✅

AvaywbK c`v_©weÁv‡bi m~Pbv  Varsity Practice Sheet ......................................................................................................... 1 MCQ weMZ mv‡j DU-G Avmv cÖkœvejx 1. GKwU avZzi Ici meyR Av‡jv AvcwZZ n‡j d‡UvB‡jKUab wbM©Z nq| wb‡Pi †Kvb e‡Y©i Av‡jv AvcwZZ n‡j H Zj †_‡K Aek ̈B d‡UvB‡j±ab wbM©Z n‡e? [DU 23-24] jvj (Red) njy` (Yellow) bxj (Blue) Kgjv (Orange) DËi: bxj (Blue) e ̈vL ̈v: †e = †e ̧bx bx = bxj Av = Avmgvbx m = meyR n = njy` K = Kgjv jv = jvj wb‡Pi w`‡K †h‡Z _vK‡j  evo‡Z _vK‡e, E Kg‡Z _vK‡e| E 2. GKwU †Ua‡bi w ̄’i Ae ̄’vq •`N© ̈ n‡jv 100 m| GwU AwZ D”P †e‡M 80 m •`‡N© ̈i GKwU myo‡1⁄2i ga ̈ w`‡q hvq| myo‡1⁄2i `yB cÖv‡šÍ Aew ̄’Z ch©‡eÿKiv jÿ K‡ib †h, GKwU g~û‡Z© †UabwUi •`N© ̈ wVK myo‡1⁄2i •`‡N© ̈i mgvb nq| c-Gi GK‡K †Uab Gi †eM KZ? [DU 22-23] 0.866c 0.333c 0.5c 0.6c DËi: 0.6c e ̈vL ̈v: L = L0 1 – v 2 c 2  80 = 100 1 – v 2 c 2  (0.8)2 = 1 – v 2 c 2  1 – 0.82 = v 2 c 2 [0.62 + 0.82 = 1]  v = 0.6c 3. GKwU B‡jKUab‡K V wefe cv_©‡K ̈i g‡a ̈ ivL‡j, B‡jKUa‡bi †eM v Ges cÖhy3 wefe cv_©‡K ̈i g‡a ̈ m¤úK© †KvbwU? [DU 21-22] v = eV m v = 2eV m v = eV2 m v = 1 2 mV2 DËi: v = 2eV m 4. GKwU e ̄‘KYvi †gvU kw3 Gi w ̄’i fi kw3i wØ ̧Y| Av‡jvi `aæwZ c n‡j, KYvwUi `aæwZ KZ? [DU 21-22] 2c 3 3 2 c 2c DËi: 3 2 c e ̈vL ̈v: E = 2E0  mc2 = 2m0c 2  m0 1 – v 2 c 2 = 2m0  1 4 = 1 – v 2 c 2  v 2 c 2 = 3 4  v = 3 2 c 5. GKwU avZzi Kvh©v‡cÿK 6.63 eV| avZzwUi †ÿ‡Î d‡UvB‡jKUab wbtmi‡Yi m~Pb K¤úv1⁄4 KZ? [cøv‡1⁄4i aaæeK = 6.63  10–34 Js] [DU 17-18] 16  1014 Hz 16  10–14 Hz 1.6  10–19 Hz 1.6  1019 Hz DËi: 16  1014 Hz e ̈vL ̈v:  = hf0  f0 =  h = 6.63  1.6  10–19 6.63  10–34 = 1.6  1015 Hz 6. 9.11  10–31 kg fiwewkó B‡jKUab hw` 2.5  106 ms–1 †e‡M P‡j Zvn‡j Gi Rb ̈ wW-eaMwj Zi‡1⁄2i Zi1⁄2‣`N© ̈ KZ n‡e? [DU 16-17] 2.9  10–4 m 2.4  10–8 m 2.9  10–10 m 2.4  10–39 m DËi: 2.9  10–10 m e ̈vL ̈v:  = h mv = 6.626  10–34 9.1  10–31  2.5  106 = 2.9125  10–10 m
2 ........................................................................................................................................  Physics 2nd Paper Chapter-8 7. 6.63 eV †dvU‡bi K¤úv1⁄4 n‡jvÑ [DU 16-17] 1.6  1015 s –1 6.63  1034 s –1 4.14  1015 s –1 4.14  1034 s –1 DËi: 1.6  1015 s –1 e ̈vL ̈v: E = hf  f = E h = 6.63  1.6  10–19 6.63  10–34 s –1 = 1.6  1015 s –1 8. 1 wgUvi •`‡N© ̈i GKwU † ̄..j Zvi cÖ ̄’ eivei 0.95c †e‡M Pjgvb n‡j j ̈v‡e Gi cwiwgZ •`‡N© ̈i gvb KZ? [DU 15-16] 0 m 0.098 m 0.31 m 1.0 m DËi: 1.0 m e ̈vL ̈v: cÖ ̄’ eivei MwZkxj nIqvq, cÖ ̄’ cwiewZ©Z n‡e| •`N© ̈ AcwiewZ©Z _vK‡e| 9. GKwU m f‡ii Ges e Avav‡bi †cÖvUb‡K k~b ̈ †_‡K V wefe cv_©‡K ̈ Z¡wiZ Kiv n‡j Gi †kl †eM KZ? [DU 13-14] 2eV m 2eV m eV m eV m DËi: 2eV m e ̈vL ̈v: MwZkw3, Ek = 1 2 mv2  eV = 1 2 mv2  v = 2eV m 10. GKwU MwZkxj B‡jKUa‡bi fi me n‡j wb‡Pi †KvbwU mwVK? [DU 13-14] me > 9.11  10–31 kg me < 9.11  10–31 kg me = 9.11  10–31 kg me << 9.11  10–31 kg DËi: me > 9.11  10–31 kg e ̈vL ̈v: f‡ii Av‡cwÿKZv Abyhvqx, wbðj fi A‡cÿv MwZkxj fi †ewk nq| weMZ mv‡j GST-G Avmv cÖkœvejx 1. 9  10–15 J MwZkw3m¤úbœ GKwU B‡jKUa‡bi fi KZ kg? [GST 22-23] 9.2  10–31 9.5  10–31 9.8  10–31 10.1  10–31 DËi: 10.1  10–31 e ̈vL ̈v: Ek = (m – m0) c2  9  10–15 = (m – 9.1  10–31)  9  1016  10–31 = m – 9.1  10–31  m = 10.1  10–31 kg 2. 2  1015 Hz K¤úv‡1⁄4i Av‡jv 3.26  10–19 J Kvh©v‡cÿKm¤úbœ avZec„‡ô AvcwZZ n‡j wbM©Z B‡jKUa‡bi m‡e©v”P MwZkw3 KZ J? [GST 22-23] 1  10–18 5  10–19 1  10–19 5  10–20 DËi: 1  10–18 J e ̈vL ̈v: AvcwZZ †dvU‡bi kw3 = Kvh©v‡cÿK + m‡e©v”P MwZkw3  hf =  + Ek(max)  Ek(max) = hf –  = 6.626  10–34  2  1015 – 3.26  10–19 = 9.99  10–19  10  10–19 J  1  10–18 J 3. K...òe ̄‘i wewKiY e ̈vL ̈v K‡iÑ [GST 22-23] i ̈v‡j-wR‡Ýi ZË¡ wPivqZ c`v_©weÁv‡bi ZË¡ cø ̈v‡1⁄4i ZË¡ †ZRw ̄Œq ÿ‡qi ZË¡ DËi: cø ̈v‡1⁄4i ZË¡ 4. KZ †e‡M Pj‡j GKwU i‡K‡Ui MwZkxj •`N© ̈ Gi wbðj •`‡N© ̈i A‡a©K n‡e? [GST 21-22; DU 20-21] 1 2 c 3 2 c 3 2 c 3 2 c DËi: 3 2 c e ̈vL ̈v: L = L0 1 – v 2 c 2  l 2 = l 1 – v 2 c 2  1 2 = 1 – v 2 c 2  1 4 = 1 – v 2 c 2  v 2 c 2 = 1 – 1 4 = 3 4  v = 3 2 c
AvaywbK c`v_©weÁv‡bi m~Pbv  Varsity Practice Sheet ........................................................................................................ 3 5. 6.63  10–19 J kw3wewkó †dvU‡bi Zi1⁄2‣`N© ̈ KZ nm? [GST-A 20-21] 300 600 800 900 DËi: 300 e ̈vL ̈v: E = hf = hc    = hc E = 6.63  10–34  3  108 6.63  10–19 = 3  10–7 m = 3  10–7  109 nm = 300 nm weMZ mv‡j JU-G Avmv cÖkœvejx 1. †Kv‡bv GK e ̈w3 Av‡jvi MwZi KvQvKvwQ MwZ‡Z ågY Ki‡j, Zvi Kv‡Q mgq g‡b n‡eÑ [JU 22-23] Av‡ ̄Í Pj‡Q `aæZ Pj‡Q GKB iKg g‡b n‡e †Kv‡bvwUB bq DËi: GKB iKg g‡b n‡e e ̈vL ̈v: e ̈w3 wb‡R MwZkxj nIqvq Zvi Kv‡Q mgq GKB iKg g‡b n‡e| w ̄’i KvVv‡gvi †Kv‡bv ch©‡eÿK evB‡i †_‡K MwZkxj e ̈w3‡K ch©‡eÿY Ki‡j Zvi Kv‡Q g‡b n‡e MwZkxj KvVv‡gv‡Z mgq ax‡i Pj‡Q| 2. Av‡jv hLb †Kv‡bv avZe Z‡ji w`‡K cwiPvwjZ nq, ZLb wbM©Z B‡jKUa‡bi kw3Ñ [JU 22-23] Av‡jvi ZxeaZvi mv‡_ cwiewZ©Z nq Av‡jvi K¤úv‡1⁄4i mv‡_ cwiewZ©Z nq Av‡jvi MwZi mv‡_ cwiewZ©Z nq G‡jv‡g‡jvfv‡e cwiewZ©Z nq DËi: Av‡jvi K¤úv‡1⁄4i mv‡_ cwiewZ©Z nq 3. cøvwUbv‡gi Kvh©v‡cÿK 6.2 eV n‡j Gi m~Pb K¤úv1⁄4 KZ Hz? [JU 21-22; BRUR 15-16] 4.46  1015 3.46  1015 2.5  1015 1.5  1015 DËi: 1.5  1015 e ̈vL ̈v: f0 =  h = 6.2  1.6  10–19 6.62  10–34  1.6  1015 Hz  1.5  1015 Hz 4. K¤úUb cÖfv‡ei d‡j AvcwZZ †dvU‡bi Zi1⁄2‣`N© ̈ wewÿß nevi ciÑ [JU 21-22] K‡g hvq e„w× cvq AcwiewZ©Z _v‡K Aa©- ̧Y nq DËi: e„w× cvq 5. cøv‡1⁄4i aaæe‡Ki gvÎv †KvbwU? [JU 21-22] ML–1T –1 ML2T –1 ML2T –2 MLT–1 DËi: ML2T –1 e ̈vL ̈v: cøv‡1⁄4 aaæeK, h = E c GKK  Js gvÎv  [ML2T –1 ] 6. GKB mg‡q †Kv‡bv KYvi Ae ̄’vb I fi‡eM wbY©‡qi AwbðqZvi ̧Ydj KL‡bvB cøvs‡Ki n«vmK...Z aaæeK A‡cÿv †QvU n‡Z cv‡i bv- †Kvb bxwZ‡K mg_©b K‡i? [JU 21-22] cøvs‡Ki AwbðqZv bxwZ g ̈v·I‡qj AwbðqZv bxwZ nvB‡RbevM© AwbðqZv bxwZ †Kv‡bvwUB bq DËi: nvB‡RbevM© AwbðqZv bxwZ 7. 10 MeV MwZkw3 wb‡q Pjgvb B‡jKUa‡bi fi KZ? [JU 20-21] 10.51m0 15.51m0 20.51m0 †Kv‡bvwUB bq DËi: 20.51m0 e ̈vL ̈v: mc2 = Ek + m0c 2  c 2 (m – m0) = 10  106  1.6  10–19  m – m0 = 1.6  10–12 c 2  m = m0 + 1.78  10–29 = 1.8711  10–29 = 1.811  10–29 m0 m0 = 1.811  10–29 9.1  10–31 m0  m = 20.56m0 8. m~h© cÖwZ †m‡K‡Û KZ kw3 wewKiY K‡i? [JUST-A 19-20] 6  1026 J 8  1026 J 3  1026 J 4  1026 J DËi: 4  1026 J 9. †Kvb avZzi Dci 200 A  Zi1⁄2‣`‡N© ̈i AwZ‡e ̧bx iwk¥ †djv n‡jv| avZzi Kvh©v‡cÿK 23 eV n‡j wbtm„Z d‡Uv B‡jKUa‡bi m‡e©v”P †eM KZ? [JUST-A 19-20] 968.42 kms–1 367.5 kms–1 283.63 kms–1 991.2 kms–1 DËi: Blank
4 ........................................................................................................................................  Physics 2nd Paper Chapter-8 e ̈vL ̈v: hf =  + Ek(max)  Ek(max) = hf –  = hc  –  = 6.626  10–34  3  108 200  10–10 – 23  1.6  10–19 = 6.259  10–18 J Avevi, 1 2 mv 2 max = 6.259  10–18 J  vmax = 2  6.259  10–18 9.1  10–31 = 3.7  106 m/s = 3.7  103 km/s 10. wW-eaMwj Zi1⁄2‣`N© ̈ I fi‡e‡Mi ̧Ydj wb‡`©k K‡iÑ [JUST-B 19-20] cøvs‡Ki aaæeK m~Pb K¤úv1⁄4 Kvh© A‡cÿK wWivK aaæeK DËi: cøvs‡Ki aaæeK e ̈vL ̈v:  = h p  p = h 11. GKwU †m‡KÛ †`vjK 0.7c †e‡M MwZkxj KvVv‡gv‡Z ivLv Av‡Q| c„w_ex‡Z Aew ̄’Z ch©‡eÿ‡Ki wbKU H †`vj‡Ki †`vjbKvj KZ †m‡KÛ? [JUST-A 19-20] 2.2 s 2.4 s 2.6 s 2.8 s DËi: 2.8 s e ̈vL ̈v: t = t0 1 – v 2 c 2 = 2 1 – 0.72 = 2  10 51  20 7  2.8 s 12. gvB‡Kjmb-†gvi‡j cixÿvq wbY©q Kiv hvqÑ [JU 19-20] Zvivi Av‡jvKel© Zvivi Av‡jvK Zi1⁄2‣`N© ̈ e ̈wZPvi bKkvi AcmviY wbY©q Kiv nq †Kv‡bvwUB bq DËi: e ̈wZPvi bKkvi AcmviY wbY©q Kiv nq e ̈vL ̈v: gvB‡Kjmb-†gvi‡j g~j cixÿvq e ̈wZPvi †Wvivi AcmviY wbY©q K‡ib| e ̈wZPvi †Wvivi †Kv‡bv AcmviY bv cvIqvq Zviv wbwðZ nb gnvwe‡k¦ B_v‡ii †Kv‡bv Aw ̄ÍZ¡ †bB| 13. •`N© ̈ eivei MwZkxj GKwU wgUvi † ̄..‡ji fi Gi w ̄’i f‡ii 2 ̧Y| MwZkxj Ae ̄’vq Gi Av‡cwÿK •`N© ̈ KZ wgUvi? [JUST-C 19-20; SUST 12-13] 0.5 m 1 m 2.0 m 4.0 m DËi: 0.5 m e ̈vL ̈v: m = 2m0  m0 1 – v 2 c 2 = 2m0  v = 3 2 c L = L0 1 – v 2 c 2 = 1 –     3 4 = 1 2 m 14. j‡iÄ iƒcvšÍ‡i `yBwU ey‡jU †Uab cÖwZwU 300 kmh–1 †e‡M AwZμg Ki‡j Dfq †Ua‡b Aew ̄’Z Nwoi mg‡qi cv_©K ̈Ñ [JU 19-20] 12 ns 12 ms 0 s †Kv‡bvwUB bq DËi: 0 s e ̈vL ̈v: j‡iÄ iƒcvšÍ‡i 2 wU KvVv‡gv we‡e‡Pbv Kiv nq| GKwU w ̄’i (S) Ges Ab ̈wU (S) aaæe‡e‡M x Aÿ eivei MwZkxj| GLv‡b, S I S KvVv‡gv؇qi g‡a ̈ †Kv‡bv Av‡cwÿK †eM †bB| ZvB mg‡qi cv_©K ̈ k~b ̈| [Note: a‡i †bqv n‡”Q †Uab `ywU GKB w`‡K Mgb Ki‡Q|] 15. Av‡jvi Zi1⁄2‣`N© ̈  Ges †dvU‡bi kw3 E Gi g‡a ̈ m¤úK© wb‡Pi †KvbwU? [JU 18-19] E = hc  2 E = hc  E = h c E = h 2 c DËi: E = hc  16. †dvU‡bi fi‡eM †KvbwU? [JU 18-19; RU 17-18] hf c 2 hf c hfc hfc2 DËi: hf c e ̈vL ̈v: p = E c = hf c