Title 5. P1C5.-Work-Power__With Solve.pdf ✅

KvR, kw3 I ÿgZv  Mastery Practice Sheet 3 18| m‡e©v”P 1800 kg fi en‡b mÿg GKwU wjdU 2 ms–1 mg‡e‡M Dc‡ii w`‡K DV‡Q| MwZi weiæ‡× Nl©Y e‡ji gvb 4000 N, wjdU Gi Rb ̈ me©wb¤œ KZ HP wewkó gU‡ii cÖ‡qvRb n‡e? [RUET 18-19] mgvavb: T = F + mg = 4000 + (1800  9.8) = 21640 N P = Tv = 21640  2 W = 43280 W = 58.02 HP (Ans.) 19| GKwU Rjwe`y ̈r cvIqvi †÷kb †j‡Ki cvwbi e ̈envi K‡i| Uve©vBb †_‡K cvwb D”PZv 50 m| `ÿZv 50% a‡i 1 MW ÿgZv cvIqv Rb ̈ cÖwZ †m‡K‡Û Uve©vBb w`‡q cÖevwnZ cvwbi fi wbY©q Ki| [RUET 18-19] mgvavb: 50%  mgh = Pt  1 2  m  9.8  50 = 106  1  m = 4081.633 kg (Ans.) 20| GK wgUvi •`‡N© ̈i GKwU mij †`vj‡Ki e‡ei fi 200 MÖvg| GUv‡K 60 †Kv‡Y †U‡b †Q‡o w`‡q gy3fv‡e `yj‡Z †`Iqv n‡jv| e‡ei MwZkw3 †ei hLb (i) GUv mvg ̈ve ̄’v w`‡q AwZμg K‡i (ii) myZv j‡¤^i mv‡_ mv‡_ 30 †KvY K‡i (g = 10 ms–2 )| [RUET 18-19] mgvavb: Lcos L-Lcos m = 0.2 kg 60 L (i) mvg ̈ve ̄’vq, EK = 1 2 mv2 = 1 2 m  2gh = mg(L – Lcos) = 0.2  10(1 – cos60) J = 1 J (Ans.) (ii) EK = ETotal – EP = 1 – [0.2  10  (1 – cos30)] = 0.732 J (Ans.) 21| 1 m Kvh©Kix •`N© ̈ wewkó GKwU mij †`vj‡Ki e‡ii fi 300 g, †`vjKwU‡K mvg ̈ve ̄’v †_‡K 60 †Kv‡Y wb‡q wM‡q †Qu‡o †`Iqv n‡jv| eewUi MwZkw3 †ei Ki hLb GwU mvg ̈ve ̄’v w`‡q AwZμg K‡i Ges hLb myZv mvg ̈ve ̄’vi mv‡_ 30 †KvY Drcbœ K‡i| [g = 10 ms–2 ] [RUET 18-19, 15-16] mgvavb: m = 0.2 kg 60 mvg ̈ve ̄’vq, Ek = 1 2 mv2 = 1 2 m  2gh = mg(L – Lcos) = 0.3  10  (1 – cos60) = 1.5 J (Ans.) E k = ETotal – Ep = 1.5 – [0.3  10  (1 – cos30)] = 1.098 J (Ans.) 22| GKwU cvwb we`y ̈r †K‡›`ai euv‡ai D”PZv 15 m| 5 MW we`y ̈r Drcv`‡bi Rb ̈ cÖwZ †m‡K‡Û UvievB‡bi †eøW ̧‡jvi Dci KZ †KwR cvwb co‡Z n‡e? [RUET 17-18; BUET 10-11] mgvavb: 5 MW = 5  106 W, GLb, Pt = mgh  m = Pt gh = 5  106  1 9.8  15 = 34.01  103 kg (Ans.) 23| 100 m D”PZv †_‡K 5 kg fi gy3fv‡e AwfK‡l©i Uv‡b co‡Z _vK‡e, 4 sec c‡i fiwUi MwZkw3 I w ̄’wZkw3 KZ n‡e? [RUET 10-11] mgvavb: e ̄‘ †gvU kw3 ETotal = mgH 4 sec ci f‚wg n‡Z e ̄‘i D”PZv, h = H – 1 2 gt2 = 100 – 1 2  9.8  4 2 m = 21.6 m  e ̄‘i w ̄’wZkw3 = mgh = 5  9.8  21.6 J = 1058.4 J (Ans.)  e ̄‘i MwZkw3 = mg(H – h) = 5  9.8  78.4 J = 3841.63 J (Ans.) H * h 24| 2 kg f‡ii GKwU e ̄‘‡K f‚wg †_‡K Lvov E‡aŸ© wb‡ÿc Kiv n‡jv Ges e ̄‘wU 8 sec ci cybivq wd‡j Gj| wb‡ÿ‡ci gyû‡Z© Ges wb‡ÿ‡ci 2 sec c‡i e ̄‘wUi wefe kw3 Ges MwZ kw3 KZ? (g = 9.8 ms–2 ) [RUET 09-10] mgvavb: T = 2u g  u = 8  9.8  0.5