de thi HSG vat ly NAM DINH 20082009

.Khi truc quay di qua trung di6rn cua thanh va thanh dang quay cleu vo'i toc do goc 0l tlii dat rlhg mQt vAt nho l€n mdt di€m tr€n thanh rdi dinh chit vaolhantr.. giet momen quan tfnh c[r]

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cdng sudt ti€u thu cua doan mach nhu Ti sO giira cuong dd dong di6n khong ddi r,,a cu'o'ng clo dong di€n cuc dai cua ddng diOn xoay chidu bing

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l .Khi truc quay di qua trung di6rn cua va dang quay cleu vo'i toc goc 0l tlii dat rlhg mQt vAt nho l€n mdt di€m tr€n rdi dinh chit vaolhantr giet momen quan tfnh csa vet d6i voi truc quay bang l/2 momen qudn tfnh cua tlanh Bo qua rnoi luc cdp Dgns ndns cua h€ tdng hay gi6m bao nhi€u lAn so voi ban diu? t

2 ChAl hd truc toa cl6 Ox cung phu'ong.v6'i thanh, gdc toa dQ O tai trung di€rn cua thanh. Thay doi vi trf cua truc quay dqc it-r.o t'rie., clai cua khAo s61 su'thay"doi 'r-rO r.n qua' tfni-r cua theo toa x cua truc quay'?

4rii 2.- (3.Q di6m) Tai hai dt.t: t yd B tr€n bd rrrdt cua rnot chAt long tinh co hai neLron scinq crr

d a o d o n g < i i e u h o a v o i t a n s d f : H z , c u n g biOn do

l.l-A,^,- +r.^., xi: r,r^: + , ,).,-.=T-62-=;l +?^ , c u n g p h a ban dlu bans Coi

dao d6ng di6u hoa v6i tAn sd f: ?S tlZ cqrg_94L40,

:ung pha bal dlu_ bang 0 Coilte'l dO i,''g

k h r r g t h a y d o i k h i t r u y e n e i l m E - h a t i ] f f i n g c n r / s B i € t k I l c r i i l r g

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gi['a lrai nsuot1-[ AB : 12 cm

L Tirn khodng c6ch lon nhElina hai di€m khong dao d6ng,ra,l kho6pg Ail? f l

2 LAy diern N tr€rt be rndt chAt long cho NA I AB va N c6ch A doan x Tim gia tri l n, : r - : I r nh6t cua x d€ phAn tu ch6t long taiX dao clong voi bi€n dd cuc fun- i

@ Hai v'+t.Mr ye M: 19 r<rrol lue'n;',uo,r@ uu

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2 Tu'vi trf cAn.bdng nh.an vAt M2 xr6ng Zcm.ttreo phuong thang dune roi tha

nhe kh6ng vdn 1oc dau thi thay vir M3 dao tl6ng di0u hda rrong kii vii-r M' vin nim -r hinr, r) v6n tr6n m[t ben.-Ctgn trqc toa d6 Ox theo phucrng thing dring, chiitu ducmg hu.6ng

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Brii (6.0 ali€m) Cho mach di€n nhu hinh irong d6 ^ r ) (.

cuon day thuan cdm 90 dO tu cdm L, tu di€n co di€n _rlnninnn_J|]' dung c va R la mot bi€n tro' Ddt vao hai dAu doan mach l-'uYY-Yuv -l

tQn gp j_o'I-_c_!geu 9o dien ap hi€u dung khOng d6i I I rt

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a) Di€u chinh bi€n tro'dd R:50 fi Viet bidu thu'c diqn 6p hai dAu tu di€n? ln q(kn(7 t g) b) Di6u chinh bi€n tro'd6 cdng su6t tiOu thu cua do4rr mach bdng 100 W Tim di€p rro.R cjo?

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2- I'hay doi gi6 triL va C tot gi6'trixac dinh rdi di€u chinh gi6tri cua bi6p trii' Tim cli6n ap hi€u dUng lon nhAt gifi'a hai di6m M vd N theo ll: Zr; Zg vd R? Xet c6c rruo.ng hop LC.d < va LCco2 >

Biii (2,0 dj6-) Mgt mach p Sgrlg-,Aie" tu' li' tu'ong LC gorn cuon day co tu' capr

!;*|q+il.S diqn co di€n aun\-r- y!)x6i nai bantq di€n vo'i hai cu'c cua nguon di€n khong

d6l.Tai tho'i diOrl t - 0, ngdt nguo,i.a-kh-6i ru clien roi noi'z ban tu di€n voi trai d-a, ;;i a,r-, jE

trong.mach co dao dOng di€n til'ri6ng l'irn khodng tho'i gian ngSn nh6t tu' luc nOi hui bAn ru di€n 'o'i hai ddu cu6n cAm d€n nang luo'ng dien tru'onglAp trung trJng tu Oier't t a"g

"a"-* f "n'r*ly.,ir.tr,rg tap trung cudn chn-r? Trong khoang tho'i gian ndng.luo.ng^di€n tru'o'ng nang lrro-ng ru.tru.o.re vd ndng lugng cli€n tu'cua mach thay ddi nhu'th€ ndo? 1,9 tu s

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