Content text 2. P1C2 (Vector)_With Solve.pdf
†f±i Varsity Practice Sheet ......................................................................................................................................... 1 weMZ mv‡j DU-G Avmv cÖkœvejx 1. `ywU †f±i A Ges B -Gi †hvMdj Zv‡`i cv_©‡K ̈i Ici j¤^| wb‡Pi †Kvb wee„wZwU Aek ̈B mZ ̈? [DU 23-24] |A| = |B| A . B = 0 A B = 0 A = – 2B DËi: |A| = |B| e ̈vL ̈v: (A + B ) . (A – B ) = 0 A 2 + AB – AB – B 2 = 0 A = B A_©vr, |A| = |B| 2. P = 2i + 2j – k Ges Q = 6i + 3j – 3k †f±i؇qi Df‡qi Ici j¤^ w`‡K GKwU GKK †f±i †KvbwU n‡e? [DU 22-23] – i – 2k – 3i – 6k –3(i + 2k ) 45 –3(i – 2k ) 45 DËi: –3(i + 2k ) 45 e ̈vL ̈v: B A A I B †f±‡ii j¤^ w`‡K GKK †f±i n‡j, = A B |A | B A B = i 2 6 j 2 3 k –1 –3 = – 3i – 6k j¤^ GKK †f±i = A B |A | B = –3i – 6k (–3) 2 + (–6) 2 = –3i – 6k 45 3. GKwU 3 gv‡bi †f±i‡K GKwU 4 gv‡bi †f±‡ii mv‡_ †hvM Ki‡j jwä †f±‡ii gvb wb‡Pi †KvbwU n‡e bv? [DU 21-22] 0 1 3 5 DËi: 0 e ̈vL ̈v: †f±i؇qi jwäi m‡e©v”P gvb, Rmax = 3 + 4 = 7 Ges me©wb¤œ gvb, Rmin = 4 – 3 = 1 ZvB jwäi gvb KL‡bvB 1 Gi †P‡q †QvU A_ev 7 Gi †P‡q eo n‡e bv| 4. a Gi gvb KZ n‡j A = 2i + 2j – k Ges B = ai + j †f±iØq ci ̄úi j¤^ n‡e? [DU 20-21; JU 20-21; JnU 17-18, 16-17] 0 7 4 –1 2 DËi: –1 e ̈vL ̈v: A B j¤^ n‡Z n‡j, †f±i؇qi WU MyYb k~b ̈ n‡Z n‡e| (2i ) + 2j – k .(ai ) + j = 0 2a + 2 = 0 a = –1 5. `yBwU †f±i A = 3i – 3j Ges B = 5i + 5k Gi ga ̈eZ©x †KvY KZ? [DU 19-20; JU 16-17; DU 14-15] 60 30 45 90 DËi: 60 e ̈vL ̈v: = cos–1 A .B AB = cos–1 (3i ) – 3j .(5i ) + 5k 3 2 + (–3) 2 5 2 + 52 = cos–1 15 3 2 5 2 = cos–1 1 2 = 60
2 ......................................................................................................................................... Physics 1st Paper Chapter-2 6. wZbwU †f±i a , b I c , hv‡`i gvb h_vμ‡g 4, 3 Ges 5; †hvM Ki‡j k~b ̈ nq A_©vr a + b + c = 0| Zvn‡j | c | (a b ) Gi gvb n‡jvÑ [DU 18-19] 12 60 25 15 DËi: 60 e ̈vL ̈v: a + b + c = 0 | a | + b = |–c| | a| = 4 |b| = 3 | c| = 5 b a c c 2 = a2 + b2 + 2ab cos 5 2 = 32 + 42 + 2 3 4 cos = 90 |c | (a ) b = 5 4 3 sin sin90 = 5 4 3 sin2 90 = 60 7. †f±i A , B I C Gi gvb h_vμ‡g 12, 5 I 13 Ges A + B = C | A I B †f±i؇qi ga ̈eZ©x †Kv‡Yi gvb KZ? [DU 17-18] 2 3 4 6 DËi: 2 e ̈vL ̈v: C = 13 B = 5 A A = 12 A + B = C |A | + B = |C| A 2 + B2 + 2AB cos = C 122 + 52 + 2 12 5 cos = 132 2 12 5 cos = 0 cos = 0 = 2 8. GKwU KYvi Dci F = (10i + 10j + 10k ) N ej cÖ‡qvM Ki‡j KYvwUi miY nq r = (2i + 2j – 2k ) m| ej KZ...©K m¤úvw`Z KvR KZ n‡e? [DU 17-18] 20 J 30 J 10 J 40 J DËi: 20 J e ̈vL ̈v: W = F .r = (10i ) + 10j + 10k .(2i ) + 2j – 2k = 20 + 20 – 20 = 20 J 9. hw` A = i – j + k Ges B = i + j – k GKwU mvgvšÍwi‡Ki `yBwU mwbœwnZ evû wb‡`©k K‡i, Zvn‡j Dchy3 GK‡K mvgvšÍwi‡Ki †ÿÎdj wbY©q Ki| [DU 15-16] 2 2 2 1 2 DËi: 2 2 e ̈vL ̈v: B A mvgvšÍwi‡Ki †ÿÎdj = |A | B A B = i 1 1 j –1 1 k 1 –1 = i (1 – 1) – j (–1 – 1) + k (1 + 1) = 2j + 2k †ÿÎdj = |A | B = 2 2 + 22 = 2 2 eM© GKK 10. j .(2i ) – 3j +[] k -Gi gvb KZ? [DU 14-15] 2 –3 1 –2 DËi: –3 e ̈vL ̈v: j .(2i ) – 3j +[ ] k = –3 weMZ mv‡j GST-G Avmv cÖkœvejx 1. A = 3 i + j + 2 k Ges B = 2 i – 2 j + 4 k | Dfq †f±‡ii Dci Awfj¤^ †f±iwU n‡jvÑ [GST 23-24] –8 i – 8 j + 8 k 8 i – 8 j – 8 k 8 i – 8 j + 8 k 8 i + 8 j + 8 k DËi: 8 i – 8 j – 8 k e ̈vL ̈v: A × B = i j k 3 1 2 2 –2 4 = i(4 + 4) – j(12 – 4) + k(–6 – 2) = 8 i – 8 j – 8 k
†f±i Varsity Practice Sheet ........................................................................................................................................ 3 2. GK e ̈w3 m~‡h©v`‡qi w`‡K 4 m hvIqvi c‡i `wÿY w`‡K 3 m hvq| Zvi AwZμvšÍ `~iZ¡ I mi‡Yi cv_©K ̈ KZ m? [GST 21-22] 2 4 1 7 DËi: 2 e ̈vL ̈v: cwðg c~e© `wÿY DËi 3 m 4 m †gvU `~iZ¡ d n‡j, d = 4 + 3 = 7 m miY = 4 2 + 32 = 5 m cv_©K ̈ = `~iZ¡ – miY = (7 – 5) m = 2 m 3. XY mgZ‡j 6i + 8j – 5k †f±iwUi ˆ`N© ̈ KZ GKK? [GST 21-22] 6 10 0 5 5 DËi: 10 e ̈vL ̈v: X Z 6i + 8j – 5k Y XY Z‡j 6i + 8j – 5k †f±iwU n‡”Q 6i + 8j XY Z‡j ˆ`N© ̈ = 6 2 + 82 = 10 GKK weMZ mv‡j Agri-G Avmv cÖkœvejx 1. `ywU mggv‡bi †f±i GKwU we›`y‡Z wμqvkxj| G‡`i jwäi gvb †h‡Kv‡bv GKwU †f±‡ii gv‡bi mgvb| †f±i `ywUi ga ̈eZ©x †KvY KZ? [Agri. Guccho 20-21; DU 18-19] 120 180 90 0 DËi: 120 e ̈vL ̈v: P 2 = P2 + P2 + 2 P Pcos = 120 P P P 2. `ywU e‡ji jwäi gvb 40 N, ej `yÕwUi g‡a ̈ †QvU ejwUi gvb 30 N Ges GwU jwä e‡ji j¤^ eivei wμqv K‡i| eo ejwUi gvb KZ? [Agri. Guccho 20-21; BRUR 19-20; CU 15-16] 40 N 45 N 50 N 60 N DËi: 50 N e ̈vL ̈v: |R | = 40 N |P | = 30 N Q Q P 2 + R2 = Q2 Q = 302 + 402 Q = 50 N 3. 10 N gv‡bi GKwU ej Ab ̈ GKwU ARvbv e‡ji mv‡_ 120 †Kv‡Y AvbZ| ej `ywUi jwä ARvbv e‡ji mv‡_ 90 †Kv‡Y Aew ̄’Z| ARvbv ejwUi gvbÑ [Agri. Guccho 21-22] 8 N 7 N 6 N 5 N DËi: 5 N e ̈vL ̈v: R 10 N 60 P 30 120 30 10 N cos60 = P 10 P = 10 0.5 = 5 N weMZ mv‡j JU-G Avmv cÖkœvejx 1. wb‡Pi †KvbwU †f±i ivwk? [JU 19-20] AvqZb Pvc †ÿÎdj KvR DËi: †ÿÎdj e ̈vL ̈v: †h mKj ivwk cÖKvk Ki‡Z gvb I w`K Df‡qi cÖ‡qvRb nq Zv‡K †f±i ivwk e‡j| 2. †KvbwU †f±i ivwk? [JU 22-23] AvqZb ˆe`y ̈wZK wefe ̄^Y©cvZ aviKhš¿ ˆe`y ̈wZK cÖvej ̈ DËi: ˆe`y ̈wZK cÖvej ̈
4 ......................................................................................................................................... Physics 1st Paper Chapter-2 3. wb‡Pi †KvbwU eÈb m~Î? [JU 21-22] (P ) + Q + R = P + (Q ) + R m (P ) + Q = mP + mQ P + Q = Q + P A .B = B .A DËi: m (P ) + Q = mP + mQ e ̈vL ̈v: wewbgq m~Î: P + Q = Q + P ms‡hvRb m~Î: (P ) + Q + R = P + (Q ) + R 4. GKwU e ̄‘‡K 50 N ej Øviv cwðg w`‡K Ges 20 N ej Øviv DËi w`‡K Uvbv n‡”Q| jwä e‡ji gvb KZ n‡e? [JU 18-19] 53.85 N 63.85 N 43.85 N 50.85 N DËi: 53.85 N e ̈vL ̈v: 20 N 50 N R c. c~. `. D. R = 502 + 202 = 53.85 N 5. DËi I c~e© w`‡Ki g‡a ̈ evqy cÖevwnZ n‡”Q| evqyi †e‡Mi DËi I c~e© w`‡Ki Ask h_vμ‡g 5 kmh–1 Ges 12 kmh–1 n‡j jwä †eM KZ n‡e? [JU 19-20] 60 kmh–1 7 kmh–1 17 kmh–1 13 kmh–1 DËi: 13 kmh–1 e ̈vL ̈v: R = 5 2 + 122 = 13 kmh–1 R 5 kmh–1 12 kmh–1 D. c~. 6. 10 N gv‡bi GKwU ej X Aÿ eivei wμqv Ki‡j Y Aÿ eivei Gi Dcvsk n‡eÑ [JU 19-20] 10 N 5 N 8.66 N 0 N DËi: 0 N e ̈vL ̈v: Y-Aÿ eivei Dcvsk = 10 cos90 = 10 0 = 0 N Y 10 N 7. † ̄avZ bv _vK‡j GKRb muvZviæ NÈvq 8 wK.wg. †e‡M muvZvi Kv‡U| NÈvq 4 wK.wg. †e‡M cÖevwnZ b`xi wVK Ic‡ii we›`y‡Z †cuŠQv‡Z muvZviæ‡K †Kvb w`‡K iIbv w`‡Z n‡e? [JU 12-13] 90 120 150 60 DËi: 120 8. 3i – 4j – 12k †f±iwUi gvb KZ? [JU 18-19] 8 11 13 18 DËi: 13 e ̈vL ̈v: gvb = 3 2 + (–4) 2 + (–12) 2 = 13 9. ej cÖ‡qv‡M m‡e©v”P KvR n‡e hLb ej mi‡Yi mv‡_ wμqv K‡iÑ [JU 18-19] 45 †Kv‡Y 30 †Kv‡Y j¤^ eivei GKB w`‡K DËi: GKB w`‡K e ̈vL ̈v: W = Fs cos Wmax n‡j cos = 1, = 0, A_©vr GKB w`‡K 10. A B = B A n‡j G‡`i ga ̈eZ©x †KvY KZ? [JU 21-22] 3 4 2 DËi: e ̈vL ̈v: A B = B A Avgiv Rvwb, A B = – B A B A = – B A 2 B A = 0 2AB sin = 0 = 0, 11. `ywU †f±‡ii † ̄‹jvi ̧Ydj 18 GKK| G‡`i †f±i ̧Ydj 6 3 GKK n‡j, G‡`i ga ̈eZ©x †KvY KZ? [JU 22-23] 60 45 90 30 DËi: 30 e ̈vL ̈v: AB sin = 6 3 AB cos = 18 sin cos = 6 3 18 tan = 1 3 = 30