Content text 5. P1C5. HSC PREP Papers 26_With Solve.pdf
2 HSC Physics 1st Paper Chapter-5 3| GKwU KYvi Dci F = (–5i – 3j – 6k ) ej cÖ‡qvM Kivq KYvwU P(–6, 7, –1) we›`y †_‡K Q(–3, –8, 4) we›`y‡Z ̄’vbvšÍwiZ n‡jv| [iv. †ev. 23; g. †ev. 23] (K) Ae ̄’vb †f±i Kv‡K e‡j? (L) † ̄av‡Zi mv‡_ AvovAvwofv‡e b`x cvwo w`‡Z †b.Kv Kxfv‡e Pvjv‡Z n‡e? e ̈vL ̈v Ki| (M) DÏxc‡Ki KYvwUi miY wbY©q K‡iv| DËi: P = – 6i + 7j – k Q = – 3i – 8j + 4k DÏxc‡Ki KYvwUi miY = (– 3i ) – 8j + 4k –(– 6i ) + 7j – k = 3i – 15j + 5k (Ans.) (N) GLv‡b DwjøwLZ ejwU †K›`agyLx ej wQj wKbv? MvwYwZKfv‡e we‡kølY K‡iv| DËi: †K›`agyLx ej Øviv K...ZKvR = 0 W = F .S = (– 5i ) – 3j – 6k .(3i ) – 15j + 5k = 0 DÏxc‡Ki ejwU †K›`agyLx ej| (Ans.) 4| GKwU KYvi Dci F = (2i ) + 3j – 2k N ej cÖ‡qvM Kivq P(2, 1, –3) we›`y n‡Z Q (3, –2, 1) we›`y‡Z ̄’vbvšÍwiZ nq| Aci GKwU F = (–i ) – j + k N, F Gi mv‡_ cÖhy3 n‡q KYvwU‡K P we›`y †_‡K R(–2, 1, 3) we›`y‡Z ̄’vbvšÍwiZ K‡i| [Kz. †ev. 23] (K) hvwš¿K kw3 Kx? (L) Nl©Y ej AmsiÿYkxj ej, e ̈vL ̈v K‡iv| (M) PQ mi‡Yi Rb ̈ K...ZKvR wbY©q K‡iv| DËi: P = 2i + j – 3k Q = 3i – 2j + k P we›`y n‡Z Q we›`y‡Z ̄’vbvšÍwiZ n‡j miY, S 1 = Q – P = (3i ) – 2j + k – (2i ) – j + 3k = i – 3j + 4k KvR W1 = F 1.S 1 = (2i ) + 3j – 2k .(i ) + 3j – 4k = –15 GKK (Ans.) (N) PQ Ges PR mi‡Yi Dfq‡ÿ‡Î MwZkw3i cwieZ©b mgvb n‡e wKbvÑ MvwYwZK we‡kølYmn gšÍe ̈ K‡iv| DËi: P = i – 2j + k R = – 2i + j + 3k S 2 = (– 2i ) + j + 3k – (2i ) + j – 3k = – 4i + 6k F 2 = F + F = (2i ) + 3j – 2k + (– i ) – j + k = (i ) + 2j – k N KvR, W2 = F 2.S 2 = (i ) + 2j – k .(– 4i ) + 6k = –10 GKK (Ans.) †h‡nZz, W1 W2 ZvB PQ Ges PR mi‡Yi †ÿ‡Î MwZkw3i cwieZ©b mgvb n‡e bv| (Ans.) 5| GKwU cvwbc~Y© K‚‡ci MfxiZv I e ̈vm h_vμ‡g 20 m I 2 m| GKwU cv¤ú 30 min G K‚cwU‡K cvwbk~b ̈ Ki‡Z cv‡i| [g = 9.8 ms–2 ] [h. †ev. 23] (K) KvR-kw3 Dccv` ̈wU †jL| (L) MwZkw3i gvb me©`v abvZ¥K nqÑ e ̈vL ̈v Ki| (M) cv‡¤úi ÿgZv †ei K‡iv| DËi: P = mgh t = r 2 l g h 2 t = 3.1416 1 2 20 103 9.8 20 2 30 60 = 3420.85 W (Ans.) (N) K‚cwUi 1g PZzf©vM I 4_© PZz©fvM cvwbk~b ̈ Ki‡Z cÖ‡qvRbxq mg‡qi ZviZg ̈ n‡e wKbv? n‡j †Kgb n‡e wnmve K‡i †`LvI| DËi: 1g PZzf©v‡Mi †ÿ‡Î, t1 = mgh 1 p = r 2 l g h 1 p = 3.1416 1 2 20 4 103 9.8 0 + 20 4 2 3420.85 = 112.5 s 4_© PZzf©v‡Mi †ÿ‡Î, t2 = mgh 2 p = r 2 l g h 2 p = 3.1416 1 2 20 4 103 9.8 3 4 × 20 + 20 2 3420.85 = 787.5 s t1 < t2 (Ans.)