Title 2. P2C2 Electrostatics_With Solve.pdf ✅

2  Physics 2nd Paper Chapter-2  U = 2.178  10–3 J (Ans.) 7| GKwU mgvšÍivj cvZ avi‡Ki cÖwZwU cv‡Zi †ÿÎdj 200 cm2 Ges evqy‡Z cvZ؇qi ga ̈eZ©x `~iZ¡ 0.4 cm n‡j Gi (i) aviKZ¡ wbY©q Ki| (ii) hw` aviKwU 500 V •e`y ̈wZK Dr‡mi mv‡_ ms‡hvM Kiv nq, Z‡e avi‡K KZ kw3 mwÂZ n‡e? [BUET 17-18] mgvavb: i. avi‡Ki aviKZ¡, C = 0kA d  C = 8.854  10–12  1  200  10–4 0.4  10–2  C = 4.427  10–11 F ii. mwÂZ kw3, U = 1 2 CV2  U = 1 2  4.427  10–11  5002  U = 5.533  10–6 J (Ans.) 8| cÖwZwU 220 V G PvwR©Z mgAvKv‡ii AvUwU †QvU †MvjvKvi †duvUv‡K wgwjZ K‡i GKwU eo †duvUvq cwiYZ Kiv nj| eo †duvUvi wefe KZ n‡e? [BUET 14-15; 11-12] mgvavb: †gvU AvqZb aaæeK _vK‡j, 4 3 R 3 = n  4 3 r 3  R = n 1 3 r †QvU †duvUvi wefe, Vs = 1 40 . q r eo †duvUvi wefe, Vb = 1 40 Q R = 1 40 . nq n 1 3 r  Vb = n 2 3 Vs = 8 2 3  220  Vb = 880 V(Ans.) 9| 2 F aviKZ¡wewkó GKwU aviK‡K PvwR©Z Kivi ci GKwU cwievnx Zvi Øviv GwU‡K PvR© gy3 Kiv nj| avi‡K mwÂZ mg ̄Í kw3B ZviwU‡K DËß Ki‡Z LiP nj| GB kw3i cwigvY 214.3 K ̈vjwi n‡j, KZ †fv‡ë aviKwU‡K PvwR©Z Kiv n‡qwQj? [BUET 13-14] mgvavb: avi‡K mwÂZ kw3 = Drcbœ Zvckw3  1 2 CV2 = Q  214.3  4.2 = 1 2  2  10–6  V 2  V  30,001 V (Ans.) 10| 4.0  10–8 C gv‡bi ÿz`a mgvb I wecixZ RvZxq Avavb 6.0 cm e ̈eav‡b A I B we›`y‡Z Aew ̄’Z| Avavb؇qi ms‡hvM mij †jLv AB Gi j¤^ mgwØLÛ‡Ki Dci 4.0 cm `~‡i p we›`y‡Z ̄’vwcZ 1.0  10–8 C Avav‡bi Dci wμqvkxj ej wbY©q Ki|     1 40 = 9  109 Nm2C –2 [BUET 13-14] mgvavb: Fnet F F 4cm 3cm 5cm 40nC –40nC  10nC  F = 1 40 . q1 q2 r 2  F = 9  109  (10  40)  10–18 0.052  F = 1.44  10–3 N Avevi,  = 2 tan–1     3 4   =  – 2 tan–1     3 4 = 106.26  wμqvkxj jwä ej, Fnet = 2Fcos    2 = 2  1.44  10–3  cos     106.26 2 = 1.728  10–3 N (Ans.) 11| evqy gva ̈‡g 50000 Vm–1 mylg •e`y ̈wZK †ÿ‡Î `ywU e„ËvKvi cvZ 0.002 m `~i‡Z¡ mgvšÍivj Ae ̄’vq Av‡Q| cÖwZwU cv‡Zi e ̈vmva© 0.08 m. MwVZ aviKwU‡Z †gvU mwÂZ kw3 wbY©q Ki| [BUET 10-11] mgvavb: mwÂZ kw3, U = 1 2 CV2  U = 1 2     0  kA d  (Ed)2  V = 1 2  8.854  10–12  1    0.082  (5  104 ) 2  0.002  U = 4.45  10–7 J (Ans.) 12| 3  10–10 C Avavbhy3 GKwU †MvjvKvi †Z‡ji †duvUvi Z‡ji wefe 500 V. hw` GiKg `ywU †duvUv wg‡j GKwU †MvjvKvi †duvUvi m„wó nq, Zvn‡j D3 †duvUvi Z‡ji wefe KZ n‡e? [0 = 8.85  10–12 C 2N –1m –2 ] [BUET 08-09] mgvavb: †gvU AvqZb aaæeK _vK‡j, 4 3 R 3 = n  4 3 r 3  R = n 1 3 r †QvU †duvUvi wefe, Vs = 1 40 . q r eo †duvUvi wefe, Vb = 1 40 . Q r = 1 40 . nq n 1 3 r  Vb = n 2 3 Vs = 2 2 3  500  Vb = 793.7 V (Ans.)