THI LÝ 2010 (TT CHÙA BỘC HN)

Lo i h": +z v& rc.cu HA uDf rV rm rrrrJ LAN Tr.ru'or uON : vAll,i Ngiy rhi: ZU3/20t0 'Ihli gian: 90 phrir ni bai gim 06 rrang I. PHAN CHUNG cl{o TAr cA rrli sINH (40 cduo rir cf,u r d6n c6u 40) cau t: Mdr con ric.rd xo ndm.ngang ou" Jo"g jie; hd, il; qu;;h "in.r "i" bing vd c6 phuorrg trinh x: A cos (cot) ;.x tinh bing cm, tfrrh bing giay(s). Bi6t"rang cri- sau nhfrrrg khodng tho.i gian birrg.nhau y1-ui"s.,r1+o itl tni o".o';'il g cria va1 c6 giri rri bdng ttr6 rrirrg c0a ld xo. N6Lr vat cd hh6i lu'o'ng 200 g thi ld xo cd OO crirr's ta: 0,4 8O Nim B. 40 NAn- c. 80 kg/rn D. 90 N/rn. * 6eu2:Mdtconlf,c,lo*nnitngung.daodgng;ffi;;"xungquanhvitrf cdrrbing.Bi6tringlfrct lr0 16' o.^Yi'if can bdng va.co v?n io9 uo "rl, hu'6'ng sang-phai. E[t trLrc roa dd ox ni'r ngang, gdc toa dQ o tai vi tri can bing vd.chi6u duong sang tr;i,Bd!ua ttroi'tuo.ng cria iJ xo. cho bi6t: lo c6 d6 cring k:90 N/ nr: vdt c6'kh6i luong rrr : roo g. phLrong trirrh clao oo,ig cr:ra vai ta, 1.*=4sin(30t)cm B. x:4sin(30t-n/2)crn r 9.*=4sin(30t-1800)cm. D. x:4sin(jgt+z) cm. cdu 3: M9t ld xo duo,c treo thing dimg, dALr tr'6n cd dinh .on oiu ouoi gdn qr-ra ndrrg. eua ndng d. vi trr cdn bing khi rd xo ddn 2,1 J'.,'. L{r:, ;: l0 ;tr;. N6; "ai q"" dong iieu i.,ou "ung quanh vi tr.i can birrg v6'i bi€n d6 3 cnr ttri ioc dQ c0a vat khi qua vi trf cd' b;;; iJ,'" srve rrvq Aur A. Khdng tfnh dLro-c vi thi6u dii. kiQri. B 60 cnr/s C. 120 crn/s ,-', ;; :.:",: cau 4: ciA st' m6t vat thanr gia d6ng tho'i hai dao ?;rit :#:roa cirrg ph*ong, cir'g rA' s6 vd co phuongtrinlidaoddnglAnlu'orld: xr=4cos(cot)cntl x2 =4Jj.or(-rr r.ni) c,n.phu.ongrri,.,h dao d6ng cira vdt ld: A. x= 8 cos (cot +116) cn. B. x = g cos (olt_ n/3) crrr. 9.*=8cos( rr,ot n16)cm. . D.,x: g cos i at+n13icr.l. { xCAu5: Mdtconl6cldxokhi v6tc6l<h6i lu.g.ngnrr thi .nrf.i'A^od6ngT1 =1,2(s),khi v6tc6l<h6i l'o.'.1r$'n' thi chu k,'T2 : 1,6 (s). H6i khi vdt-c6 ktroi tLrqni,n = nr, + mz rhi chu kj, 1- bing bao A. T:?,8(s) g. T = 2,4(s) C, T: 2,0(s) * D. T = 2,g(s) ciu 6: M6t corr ,r" j:, i: dao dQrrg di6u L,oa, ntiu ld .xo c6 dQ crtlng ld g0 N/m itri "nu kj, dao d6ng ld 0,2s. Lt'y n2 = 10. Kh6i lLlong cr:r"a vAt ld: 4.200 S B,t 80 g C. 100 g D. 800 g. ciu 7: Mdt con i6c ld xo g6m qLra ndng ".?r'",*g c6 d6 crlirg 40 N/nr. Keo.qua ndng ra l<hoi vi rri !]: j;t i;f,j:' tha nhe-cho iuo obn! didLr hoa ""e qr.ir' vi rrr cdn ba;g. co. riang dao d6ng A. E = 320 (J) B. E.: 6,4. rc-2 e) g, E,:: 2 lo, f.li . D. E = 3,2 (J) cau 8: M6t s6ng co lroc hirrh cos lan rruvdn thi khodng .a.[r.gio nhdt girra i ui p1,An rr]. nim rr6rr phu'ongtruydn s6ng c6 vdntdc dao dong bi'g_nhau rd - Jqrr rrrrql 5rLI4 Irdrr Priilrl A. U, B,,1' C. ),/2 D. .u4 Cdu 9: Mdtsongco'hocc6 phuongrrinh daod6ngraiA[,"N ldy:4sin (t.z/6); yriph bing prm; t tinh bing gidy (s). l'ai tho'i di6nr t; li d6 cL'ia N le 2.6 n1n vd dang Lang rhi sau d6 3 s li cl6 cria N id: - "D ' 'D 'lr'r "uq uu J J A.2mm B. 3 nrm. Cdu l0 : Do to crla dm gin lidn v6'i A.cu'dLrg dd drn B. bi6n d6 6m C. rAn sO D. * 2ntm. D. mfic cLrdrg dd 6rrr C. 2mni. v6prt CAu 1l: Trong hi€n tLro-ng gia.o thoa s6ng nu'6'c, tai hai ditirn A vd B ddt c6c ngutin-y]1gl& hop c6 dang y = a cos (l00nt) v6'i a tinh bing cnr, t tinh bang s; t5c d6 trLrydn s6ng trdrr mdt nLr6'c v: I rn/s. Bitit AB = I I crn.Ciri'a hai didrn A vd B c6 sti tlu'd'ng hypebol md cdc di6rn nirn tr€rr d6 dao d6ng manh nh6t ld : A. I I dud'ng. B. l0 dtrb'ng. .C.21du'drrg D. 5 du'd'ng. CAu 12: M$t doqn rnach gdrn diOn tro thuArr R :20A rnic 'rr5i ti6p v6'i tu diOn c6 di€n dr;ng C = 20 pF. Hai diu doan nrach duo-c duy tri diQn rip u: Us cos (rr.tt) vo*i a thay d6i dLlo-c. Khi thay dtiia.rthi cud'ng dQ dong di6n hi0u dung A. lu6n kh6ng ddi. B. lu6n ludn tIng. C. Iudn lu6rr gidrn. D. tdrrg l€n khi atdng vi giinr di klri a.rgiAnr. Ciu 13: MQt doan mach g6m diQn.trothuAn R:80Q mic n5i tiiip v6'i cu6n ddy thuArr cAnr vA c6 h0 s6 tU'cdnr L= 2/n (H) Hai diu doqn m4ch dr-ro-c duy tri diqn 6p u : Us cos (rot) v6'i ar thay d6i duo-c. Cud'ng dQ ddng di€n l€ch pha so v6'i diQn dp d'hai dAu doan nrach ld n /3 (rad) khi: A, @: aA r Ji (racl/s). C. o)= 40 Ji ln (rad/s) B. a: Jl Aon (rad/s). D. at:801n .6 (rad/s). CAu 14: Trong rnach diOn xoay chiAu khdrig plrAn rrhiirrh R- L- C ; n6u U61: 4U66 thi so v6'i ddng di6n, di6n rip gifi'a hai dAu doan nrach s6: A. Cing pha C,'36rrr pha B. TrE pha D . ILrdn vu6ng pha nhau :' 'l' CAu 15: Cho mach didn nhuhinh vE. Trorig?b "rOn ddy lA tlruAn cArn c6 cl6 tu cAm L: I/2n (l-l). tu di€n c6 di6n dLrng C: lU-/z (F) vd tr6'thuAn R = 50 6O Oat vdo haidAr.rdoan mach A, B di€n dp xoay chi6u c6 gie tri hieu dung 200V. tAn s0 f = 50 Hz. Ei6n iip hi6u dung UMs gifi'a hai di6m M vd B bbng: A. l00V' c. r4l v Cfiu 16: Cdng suAt cia m6t nriiy phiit di6n xoay chi€u ld l_00kW, duo-c truyAn t6'i noi ti6u rhu tr€n dud'ng dAy c6 di€n tr6'bdng 10f). Di6n dp hi€u dung giii'a hai cu'c cia rn6y ptr6t la l0kV. Cdng suAt hao t6n tr6n dud'ng dAy ld: A.0,5kw B. lkw c. r00w D. 2l(W CAu 17: MQt cuQn ddy c6 hQ s6 tg cilm L = J,6 15 n (H) du'o-c rnic vdo nrang di€n xoay chi6u c6 giri tri di€n rip hi€u dirng 220V vd tAn sd 50H2. N0Lr h0 s6 cdng suAt bing 0,2 thi cu'drrg d0 dong diOn hi6u dung qua cudn ddy sE ld: A. I,OA 8.2,2A c.4.4A D. I,4A Cf,u l8: M6t dong di6n xoay chiAu c6 bidLrthrirc i= 5 sin (l00nt + nl3) (A). Ki5t ludn ndo dLr'6i dd1, ld khdng dring ? A' Cuorrg dQ ddng di€n hiOu dung bing 5A B. TAn sO ddng di6n bing 50Hz B.200 v D. 282 V RLC zffil-+s MN C. Bi€n dQ dao ddng bdng 5.A. D, Chu k! dao ddng 0,02s CAu 19:.PhAn rirrg cira mQt nr6y phdt diQn xoay chi€u g6m l0 cdp. cti6n ddy, nrSi cudn ddy c6 5 vdng, PhAn cArn ld roto gdrn l0-9Ap cLrc. quay.v6'i vAn t6c kh6ng dOi 300vong/phfit. Tn'th6ng cLrc clai qLra nr6i vong dAy ld 3,1 I .10-2 / ru (Wb). SLrAt didn d6rig tLr cArl hi€u dung cira m6y IA: ^.220Jrv B. 220V c. r lOv D. I l0Jt v Ciu 20: M6t doan nrach g6m diQn tro- thuAn R = 50O nric nOi ti6p v6'i cudri dAy thLrAn cAm c6 h€ sd tu cAm L: 159 nrH vA tu diQn c6 di€n dLrrrg C = 31,8 pF. Hai dALr doan'rnhcli dLlo-c duy tri di6n 6p n = I20 cos (100zrQ (V) . Tdng tr6'cila doan mach ndy ld: ,\. 50 Jt f) B. I00 f) C. lOO\D O D. 50 f) CAu 2I : M6t rnach dao d6ng c6 tu di€n C = 2.10'3 ln (F) vA cLrdn dAy thuAn cArn L. Dd tAn s6 dao 2 d6ng di€n tr)r' tlorrg mach bdng 500l-lz thi L phdi co gid tri ld: A. r/500 (H) B. 5.l0-4Ft c. l0-r in (t{) D.l0-r Dn (t) Cdu22: Phdt bidu ndo ld drlng khi n6i vA su bi6n thi6n rJi€n tich cira tu tJi€rr trong nrach dao d6ng. A. Ei0n tfch cria tu di€n dao cl6ng didu hod v6.i tAn sti g6c , = JTC' B. Ei6n tich bitin thi€n theo lrdnr s6 mfr rheo rh6.i gian C. DiQn tich bi6n thi€n tLrAn hodLn theo tAn s6 g6c ol. .i " D. Ei€n tfclr crlra tu didn dao d6ng diAu hod v6.i tArr sd f : ;E cdu 23: M6t mach dao ddng gdm cLr6n day c6 d6 tLr cirn L vd tu di6n c6 di€n dung c thLrc hidn dao d6ng di€n tu tu'do. Didn tich cr,r'c d?i trdn nr6i ban tLr ld Qo vd cirdrg dd dong didn cu.c dai rrong rnach ldi Is. ChLl kj,dao d6ng di€n ti1crla mpch ld A. T: Zr&- I )o A.L= ' lt 2r B. T: 2nQolo. B.L=l H 8n C. T: znlY eo D. T : 2nLC D.L= L H 4 cau 24: M6t nrach dao ddng LC g6rn cLr6n ciay thudn cdnr cd dd tu.cdrr L : I t vd m6t tLr di6n 2n 1 c6 di€n dung C : lpe. TAn s6 dao d6ng ri6ng cira rrach ld n A.5 MHz B. 0,5 It4Hz. C.l0 MHz. D.50 MHz cAu 25: M6t dao ddng di6n tir LC ly tu'6'ng c6 g = ?prF. SaLr khi kich thich cho h6 dao d6ng, didn 7' tfehbi6'thid'rheoquylLrar q=z,5cos(2-,103nt)(rrc).cu6ndaycdd6tucdrnbang c. L: I H E ciu26: Trong thi nghi6m Y-dng ve hicn tLro-ng giao thoa 6nh sdng, ngud.i ta dd lot d6ng thd.i hai bri'c xa d6 vd larn di q,a c6c khe hep neri tren r#ridnh giao tirou tu do duo-c dQ rQng crja van do vd vdn lam lAn luot Ia 0.64 rnm; 0,48 riirn.ed r0ry11a vnnfgiao thoa la l2 nrm trri s6v?n sring Id A. 37 vdn s6ng. B. 44 vdrr siing. C.:l uan ,irig. D.43 vdn s6ns. cdu 27: Trong thi nghi6m giao thoa uo'i th. IAng, khe 5ou'q.,.rrier, ri"gii?g.hin, s6ng tr6'g (0,4prn < l' < 0,75pr',]l B?rQrrg quang ph6 bac I trdn rniin trjrc dALrao or:q.;o.ioi r I4n, dich rndn ra xa hai lihe th€rn 40cnr thi bd rdng qlrang pti6 bac I rrdn nrdn do du.o-c ld 0,g4nrnr. Khoing ciich giii.a 2 lche SrSz ld: A. lmrn B. l,2mm C. l,5mm D.2nrm cau 28: Khirn6t vat hfry th' iinh s6ng phdt ra ti.in6t ngudn thi nhi6t d6 c0a v6r A' cd thd co gia'ri fet I{}. B. cao hon nrridt dd crra ngLr6n. !r bang nhigt dQ cria 'gu6n. D. thap ho'' nhlet ao.,r. igra" CAu 29 : Tia h6ng ngoii .6, A. budc s6ng IdLr hon bu.d.c sting ciia dnlr siine nhirr rh6v. B. bLrd'c s6ng ld'n hon bLr6.c s6ng cira s6ng vdluytln. C. bLrd-c s6ng nhd hon bu.d.c s6ng cL"ra tia iil ngoai. D. bu'6'c s6ng nhd hon bLr6.c s6rrg cria ria X. cau 30: Khi chi6Lr rn6t chirrn sang song song qua mdt b€n cila ldng lcinh ta qual s6t dLr.o-c hi6rr tu'orig tiin s6c g6nr 3 chirrn s6ng mdu khic nhJu,'atp;6;;;" o-i,rn rLr.giirn dAn cira ",ricr'rii,'.ll chilng ld: A. Vdrng, Ianr, iuc B. Lapr. luc. r,dng C. Lqrc, lam, vdng D. Vdng, luc, lam Cdu 31: Chi6u rn6t chirnr tia til ngo4i c6 bu6'c s6ng l47nrn vio m6t quA cdu bdng d6ng c6 l6p. Sau rndr thd'i gian nh6t dinh cli6n th6 cu'c dai cria qLrd cAu le 4V. Gid'i han quang di€n c0a d6ng ld A.0,3l2pm B.279nm C.0.423pnr - D.325nrl Cho bitit: h: 6,625. l0-3a Js; c : 3.108 rl/s; e : - 1,6.10-re C. CAu 32: Khi chi6u hai dnh sdng c6 tAn s6 fr = 2.10r5 Hzvitfz:3.10t5 HZ viro rn6t kim loai dirng ldrn catot cfia t6 bdo quang diQn, riguo'i ta chi thAy ti sii giLi'a vdn t5c ban dAu cuc dai cdia c6c electron quang diQn brit ra khdi catot ld bing 2. TAn sd gioi h4n cL'ia kirn Ioai d6 ld: A, 1,95 .1.015 Hz B. 1,45 .10r5 Hz ' c.0,76.10r5 Hz. D.1,67.10r'5 Hz CAu 33 : Trong hi6n tuo. ng quang di6n ngodi, €lectron quang diQn brit ra khoi bA rn[t kinr loai c6 vAn ttSc ban diu cr,r'c.d4i vor,ar. vd dug-c bay tlring vdo tt trudng dALr theo hu6rig xi6n g6c v6'i dudlg sfrc ttL. Khi d6 chuyOn dQng cria h4t €lectron trong tit trirdlg ld A. dud'ng tron c6 b6n kinh B. dudng parabol C. du'ong xoin ld xo D:rm6t nh6nh cira duo'ng parabol Cdu 34 : Hign tuo.'ng ndo sau dAy lA hien tuo-ng quang diQn ngodi A. h4t electron but ra khoi kinr loai khi rrung rr6ng B. h4t electron birt ra kh6i kirn loai l<hi c6 lon ddp vio C, hat electron bfit ra kh6i kim loai klri cti cdc ngtrl'6p tfl ttrong tdc nlrau cILr rnarrh D. hat electron bfit ra khdi kim loai khi c6 6rrh s6ng thich ho-p chi6u vdo. Ciu 35: Dd tlii ndo dLr6'i ddy v€ dirng du'drrg ddc trr.rng vdn - ampe crla t6 bdo quang di6n? Uno 0 Unx 0 A. B. 0 UrK 0 C. D. CAu 36: Chi6u chirm tia s6rrg dorr sic gdrn cilc phdton c6 ndng luo-ng lA 3,5.10-reJ viio cat6t crla mdr t6 bdo qLrang dign ldm bing kirn Ioai co c6ng thoiit di0n tdr Ia 3,1,l0-reJ. Hi0u di0n th6 Uas hanr khi d6 la: A. +0,25V B. -0,4V C. -0-25V Ciu 37: Hi6Lr di€n thil giii'a ani5t vd cat6t crjra mdt 5ng ronghen td ',1 tia ronghen rnd dng d6 c6 th€ phdt ra ld A. l" : 10.10-l rrn B. /, = I 0,352. I 0-r2tn C.l.:10.10-r2rn D.I= 10,532.10-rrm CAu 38: Cdu trA ld'i ndo ld khdng thing khi bdn vA hi6n tu'o-ng qlrang di6n trong vd lri€n tuo-ng qLrang diQn ngoAi? A. D0u gidi ph6ng dugc c6c electron ,'' B. D€u c6 bu'6'c s6ng gi6'i han lo. C. Bu5'c s6ng gi6'i han crla.hi€n tu'o-ng qllang diQn trong c6 th0 thuOc virrrg hdrrg ngoai. D. Nln-e lu'o-ng cAn thitit de gini phfrng electron tlong khdi bdn din lo'n lrorr cdng thodt ctja electron ra khoi kirn loai. CAu39:BdnkinhquldaoBohrthflnirnli 13,25A0,Mdtbenkinhkhdcbd'ng4,77.10-r0nrsEfrng v6'i b6n kinh qu! d4o Bohr thri'. 4.2 8.4 c.3 D.6 D. f0,4V l20kV. Bu6'c s6ng ng6n nhAt cia Cdu 40: Anh sdng nhin th6y chi6u vdo chAt ndo sau ddy g6y ra hi6rr tu'o-rrg qlrang diCn trong: A. di6n rndi B. kim loai C chdt bzirr ddn D. ii kini rr. PHAN Rr0NG (10 cAu) Thf sinh chi rluqc lim m6t trong hai phan (phdn A hodc B) A. Theo cltu'o'ttg trinh Chuirt (ri c6u, til'cni lt ttan cil soj cau 41 : M6t con l6c,lo xo nirn ngang.dao_ddng didLr hda xungquanh vi tri c6rr bing. Bidt rirrg 1ic r:0 var 6'vi tri cdn bing va c6 v6n i6c50 cmTs hLrd-ng s^11_sgrrii,g4t ir,,.;;;;o 6_-,;il;;";;; g6c toa d6 O tai vi trf cdn bing vd chi6u du'ong tung-sihii.siiiLra kh6i lLro-ng c0a lo xo. Cho bi6t: lo c6 dd cflng k : 250 N/ rn; vdt c6 khdi lirong m-= 40-0 g Phuon! rrinh dao d6irg cila vdt ld: A.x=2sin(251)cm .8. x=2sin{25t-n/2)cnt C.x=2sin(25t-1800)cnr. D. x=2sin (z1y+n) cm. Ciu 42: Con l6c lo xo treo thing dring, r4i noi c6 gia t6c tr"ng iriOng g : 9,g m/s2. Khi qud cALr can bing, lo xo gidn m6r doan 4c;. co;iac dao dQng diau hoi, trri crru kj,dao d6ng rd: A. 9,87(s) Q. 0,1(r) .c. 0,98(s) D.4(t cau 43 : s6ng 6m c6 tAn st5 450H2lan truydrr v6'i vfln'tdc 360rn/s trong kh6ng khi, Giri.a hai di6m ciich nhau 1,6 m tr€n-phu.ong truydn thi chfing dao d6ng: A. Cirng pha. B. Ngu.o-c pha. C.t1cn.pnZntZ D.LQch pl"ran/2. cdt 44: crich n6i nio sau.dd,1' li kh6ng dring klii do' cap ddn drih ,a,.,gao.,., :t; " - A .c6 m6t bLrd'c s6ng xiic dinh _B- ,ap r.,-olp mqt s6 bu.oci6ng *a. oinrr. C. khdng bi tdn sdc qua ldng kfnh .,, d O n,ari Oon ,i. nhAt dinh 7 cau 4s:Trong hi6n tLrgng giao thoa s6ng nu6'c., tai hai di6rn M vd N ti€n inat nLrd.c det c6c ngudrr s6ng k6t ho-p dao dQng d6;rg pha vd co tA"n s6 udru:'o Hr.:i'rcr'a"arir.'a,r; **,'n;i;i€nr dao d6ng cd bi€n d6 cu'c dai ciiclr nhau gArr ntr6t ta l,g cm. [ni oo toc oE truyen sdng ld: A. 54 cm/s. B. 16,6j cm/s. . C.l0,g m/s. D. l0g cm/s. can 46: Ndnr luo'ng ti:truo-pgqrc4#usl-dAv cria.m6r mach dao d6ng di0n rD ru,do LC bi6n rhi6n { r<f.ong otaLirr;a tneo trroi gi;ri. B.;rd; ;;;;iloliloi giun v6.i tan s6 r. c.didLr hoa rtreo thdi gian voi tAn s6 r/2. t.;id; il;;i;;; ti.,oi giun vo.i tAn s6 zr Cdu 47: Trong thi nghi€rrr Y-dng vd jhidn tuorrg giao thoa iinh sdng, trdn nrdn 6rrh giao thoa rrgLr.o.i ta do du'oc khodng ciich-tur,'6n sdng trung tarn (va-n cnrnn giral den uan s6ng bac l0 la 3,6 mnr. Khi d6 vi trf cira v6n s6ng b6c 6 ld 4.2,4 mm. B. 2,16 nrm. C.2,16 crn. D. 1,96 mm. cAu 48 : Mfc cu6n ddy c6 R : 40Q vd, L= 0,3/n (H) vdo di€n rip xoay ch idLr u =200 .12 cosl I 00n1) V6n, nhigt lu'o-ng t6a ra tr€n cLr6n d6y trorrg I phrit li ' I A. 9186,6 cal B. 3g400 cal C. 9216 cal D. I t520 cal C6u 49 : Gioi ha.n quang di6n phu thLr6c vdo A' van t6c ban lldu cL'c dpi cira erectron quaxg di0n bfrt khdi ba r,at kinr roai. B. b6n chdt cLia kini ioai dLr.o-c einlr siing cihi6Lr vdo. C. bu'6c s6ngia rinh sang.f.ii6, uJo U"d ,r.,at tinr tor.i. D. cuong d6.rinh siing chi(5u vdo bd rndt kirrr loai. Cdu 50 : K6t luan naokh6ngtlilng kiri n6i vd hi€n tLr.o-ng quang din? A' HiQ.n tLrorg q.r.u,ls aa,' ra rTie,,, 'trile'.i'ar b;;;;;,;;'oJ'., i,r?"n di€n 116. rhdnh da, didn khi bi chieu iinli siing thich ho-p. 3 *el,'^1^."1Y^:-TigdSnldhi6nfr-ro-ngelectronbrl'tklioi kh6i bandinl<hi bi c,tri€usdrig. u' D€ hi€n tu'ong quang d5ri xay ia duo-c 6'rn6t ch6t bdn d6n trri tAn so cr]a bric ru "i.,idu vdo b6n ddn d6 cdn phAi Idrr hon m6r gi6 tri x6c dinh. D' Gid'i han qirang dan crla m6t bdn din ld bLr6'c s6ng ng6n nhdt cira 6nh siing co l<ha nang g6y ra hi6n tuong quang AAn O.ctrAt aj. l Th_eo chu.ong trinh NAng cao (10 cfru, ti cAu 5l d6n cAu 60) cAu 5l: M6t rdng roc c6 mdn men qLriin tinh ooi voi trl,"-qr,.v'.0 dinh li l0i<-e.nrr, QLra1, d€, vd.i t3c {o. la 60 vong/phrht. D6ng ndng qLray cira rdng roc IA : A. 197,39.t B. t9.73 J C. 39,401 D. 3g4J Ciu 52 : l\{6t d-ia trdn ddng chAt c6 brin kinh R : 0,5 ni, khSi luo. rrg rn : I kg quay ddu xung cluanlr truc quay c6 Olnh vudng 961v5'idia vd di qua tAnr cira dia. E6ng ndrrg quay cira dTa lit2.Z5itflllal d6 quay bing : A. 60 rad/s B.6 rad/s C. 12 radis D.24radis CAu 53: Mdt dla trdn cArr du'o'c ldm bing sdt vd nhdrn d6 rn6rnen qudrr tinh cia n6 c6 giri tri cLrc dai. D.i0u niy c6 th6 ldrn duo-c bing cdch A. phAn trong dTa lAnr bing nhdrn, phAn [rao quanh lAm bing s6t. B. phAn trong dTa ldm bdng sit, phAri bao quanlr ldrn bing nh6rr. C. Dirng c6c l6'p sit ve nh6m xen k6 nhau.i D. Dirng hai tArn sit 6'rn6t tr6n vd mhr dLr6.i.vd tArn nhdm ninr 6.gifra. CAu 54: Hai vdt rfn A vd B quay vdi clQng rrdng quay lAn lu'ot ld 8., vd 8,,. M6nren qLrdrr tfnlr cira AvdBOOi vOi trllcquayld 1,vd 1,,.N6u I.o=ln/4 vit E.t=l001t,thi ti s6nr6mend6ngluong ( L.o) crta A vd nr6nren ddng luo-ng ( I") cira B ld 4.25 CAu 55 : Di€u ndo sau d6y lA khdng ihing khi n6i vd s6ng dnr? A. S6ng dm lri s6ng $oc co'hoc truy6n duroc trong cdc mdi trud'ng vAt ch6t k6 cd chdn khdng. B. S6ng dm c6 tAn s6 nim trong klioAng t[' l6Hz d6n 20000H2 tlii tai con ngud.i ngtre tnAl Erro-c. C. S6ng dn, truyAn trong nrdi trudng riir, long, lchi. D. Vdn t6c truydn Arl phu tlruQc nlriQt d0. CAu 56: Clro m4clr di6rr nhu hinh vE, trorrg d6 cuQn d6y thLrArr cdnr c6 cXd t1r cArn L: l/n (l-l). tLr di€n c6,di6n dung C : Z.l}-a ln (F) vd tro'thuAn R = 50.,6o. nat vdo hai dALr doan nrach A, B hi€u ditn thti xoay ctri€Lr rr : I00 cos ( I00 nt t-nl6 ) (V) thi cud'ng dd dong di€n qua doan mach ld : A.i:cos(l00zt+T/6)A B.i:cos(l00rd+tt/3)A R __L-_- g C. i: cos(l00lrt -1t/6)A D. i: cositoont 1,t 7@F-+n MN CAu 57.: Hai hga 6ni !i6n tit5p do rnQt dAy ddn ph;lt ra c6 tAn sO ho'n kdm nhau tit 56H2. Hoa d'r tlrrjr. hai c6 tAn s6 Ia B.5/4 L.) D.1/4 A.28Hz B. 56 Hz C.84 Hz D.l12Hz Cdu 58 : Phiit bi6u ndo ld ctfing khi n6i vd s6ng di6n ru ? A. S6ng di6n til ld song ngang vd truyin cluoc trong rnoi nr6i (ru.i'ns. B. s6ng di€n tu nrang theo ndng luorig vd khOng bi nr6i rrLrdrig hAp thu. C. S6ng di6n tiL c6 vdn t6c phu thurdc bu6c s6ng. D' Sdng diQn tt kh6ng bi phAn x4 vd khrlc xa tai m6t ngdn cdch gi0a 5ai rn6i rrudng. CAu 59: Hai b6ng ddn so-i dOt cO Rl=R2:80f) rnic song song rOi nOi tiep v6'i nr6t tu di€n C saLr cl6 ''' ' : "^ r:100J2 cos(I00d) Vdn, khi d6 Zg:3Ae. Nhi€t lu,ong rda ra tr6n m6i den rnac vao nguot'l dlen t trong 20 phrlt ld A. 192 kJ B. 96 l(J C. 384 KJ D. 768 kJ Ij. Khi li t16 bing nr6t phArr ba bi€n d0 thi A.4E/9 B. 8Ei9 c.3Et2 D. EIg CAU 60 : Ndng luo-ng cfra rn6t vdt dao d6ng di6Lr hod ld ddng ndng cira n6 bing : Htit tA/ 2D \./ 3B .,t 4D '/ 5c ,/ 68/ 7Ci 8B 9Ai o 10D " 118 " lzD 13A ' t4c " t5A : 168 .' l7c 4 18A .7 198 jji 204 .i ztD 22D 234 248 25Ij g 26A c 21[ . 36C,,, 28D ,/ 294 'i 308 3lB " 32D t 33C 34D - 358 . 378 38D 39C ."/ 40c 4lA 428 43A / 448' 45D * 46D./ 478 " 4gc e 491' \ 508 t 5tA 52B 53A s4c 55A 56t) s7D 58A s9B 608 oAp An ntON vAT LV Kv THI 'fHIJ LAN O 4 (_ CHU !: lor'' [L .' ' I. PhAn chung tu cdu 1 d6n h6t cau 40: dAy ln phAn bit buQc aOi vOi rnoi thf sinh. 2, Phdn ri€ng: Chi chon mQt trong hai phAn A hofc B. N6u ldm cA hai phAn coi nhu' pham quy ve kh6ng chAm di6rn phAn ri6ng. V,f,&lrt, TRI-rNG rAna edl UUONc vAro Hoa rnAnc LoNG xv rnr rnrt IAN rsu oz rur0rq : v4T Li' Ngiy thi: 0l llllz0rc Thtri gian: 90 phlit C.3 Hz D.4,6 Hz Pe mt gdm 07 trang L PHAN cHUI{c cHo rAr cA rHi sly{ (40 ciu, rir ciu I tt6n ciu 40) CAu 1: Mdt con lic lo xo nim ngang voi lo xo co tl$ cung k:45N/m vd hon bi c6 kh6i lu,o-ng m. Hon bi dao ddng diiiu hoa voi bi€n dQ 2 cm vd gia tOc c6 tri s6 dd lon clar cuc clai bang lg m/s2. Bo qua h;c cAn. Kh6i luong cta hon bi ld: ' A. 0,075 kg 8.450 g C,50g D. 0,25 kg. Ciu 2: Dit vio hai diu tu di6n m6t di€n iip xoay chidu c6 giri tri hi€u dung U kh6ng OOi va tAn sO 50 Hz thi cudng dQ hiQu dung qua tuld2.4 A. DC cuong cl6 hidu dung qua tu bing t.2 A thi tAn s6 cia dong dign phdi bing: 4.25 llz B.50 Hz C. 100 Hz D. 200 Hz Cdu 3: M6t vat dao tt6ng di6u hod voi bi6n d6 4 cm, Khi n6 c6 li d6 2 cm thi tdc d6 ld I m/s. TAn s6 dao dQng bing : A. I Hz B.l,2Hz CAu 4: Mdt vdt dao clQng di€u hda xung quanh vi trf cAn bing v6i phuong trinh dao d6ng ld: x : 6 cos( 20t + 2v131; trong d6 x tfnh bing cm; t tinh bing giAy; g6c rga do rai vi rrf cdn tring. Thoi gian v{t di duo. c qudng duong bing27 cm k6 tir rrjc bit?iu jaJdong la: ' A. 71160 (s) B. 9nl80 (s) .C. 5rl40 (s) D. I 3;/120 (s) Cffu 5: K6t luAn ndo kh6ng thing khi n6i vd hiQn tugng quang d5n? A. HiQn tugng quang din ld hiQn tuqng chAt ban dAn chuy6n tr.t cn6t c;ich cli€n thdnh ch6t ddn di€n khi bi chi6u iinh s6ng thich hqp chi6u vdo. ? Ileltugngquangd6nldhigntuongelectronbtnrakhoi t<hOi Uand5nkhi bi chi6usring. C= Dl hi6n tugng quang d6n xdy ra cluqc o mQt ch6t brin d6n thi tAn s6 ctia birc xa chi5u vAo bdn dAn d6 cin phdi ldn hon m6t giri tri xdc dinh. ?.liiel tuong quang dnn ld h!€n tugng giAm di6n tro cua chdt brin d6n.khi c6 :inh sring thich hop chi€u vio. Cflu 6: S6ng truydn tgi mit chdt long vdi budc s6ng 0,8 cm. Phuong trinh dao cl6ng tai ngpdn co dang us = Scostot (mm). Phuong trinh dao ddng tai di€m M cdch O rnot doan 5,4 cm theo phuo.ng truydn song ld : A. Uu = 5cos(rot + n/2) (mm) B. Uu = 5cos(ror + 13,5 n) (mm) C. l.JM = 5cos(ort - I3,5r) (mm) D. Ur,l : 5cos(ort - l0,gn) (mm) Ciu 7: Cho mach dign xoay chiAu g6m di€n trd thuAn R = l0 C), cu6n ddy thuin cdm c6 h€ s6 tu cdm L = 0,21r (H) vd tu C:318 pF, tAt ca dAu mic n6i ti6p vcri nhau. N6u bi6u thuc cua dien dp hai dAu tu di€n co dang u6 = 50J2.ot (l00nt - 3 n 14) (V) thi bi6u thrlc cua euong do dong di€n trong mach ld: Ciu 8: Mdt ddy ddn hdi r6t ddi c6 diu A dao d6ng vdi tAn s6 f co giit tri trong khoang ti: 22 Hz d€n26 Hz vd theo phuong vu6ng g6c vdi soi dAy. Vdn tdc truy6n s6ng tr€n ddy li 3 m/s. MQt di6m M tr6n dAy vd cdch A mdt doan 28 cm, ngudi ta thAy M tu6n dao d6ng l6ch pha vo'i A m6t g6c Lg = {2k+ l)n/z v6i k = 0, +1, 12, .:. Budc s6ng cria s6ng rr6n ddy ld A, I 1.5 cm B. 13,64 cm C.A,l24 m D. 0,13 I m CAU 9: MPch dao tl6ng g6m tr,r di6n Cr vd cuQn cdm L s€ dao ddng voi chu k! T1 thay ru tr€n bing tu c6 di€n dung C2 thi chu k! dao dQag bia mach ld T2. Chu kj, dao d6ng crla mach khi thay ru thAnh bd tu g6m C1 mic song song vdi Cz ld A. T: T,T, T, +7, B. T: A. i : 5 JTcos (l00nt - 3it/4 \ (A) C. i : 5 Ji cos(l0Ont + 3zrla ) (A) Ciu l0: Cho mach cli€n nhu hinh v6: R = 30Q, cu6n dAy thuin cAm c6 cdm khrlng Zr = R vd dung khring k= 2R. A. dr - 25 cm; d2 :20 cm. C.dr = 25 cm; dz=21 cm. B. i = -5 J2 .ot l00nt (A) D. i : 5 J2 cos {l00nt - r/a (A) c.r: -L- ,,lrl + rr' D. T: q.'J ,lr,'+rl ffiH RLC Di€n ilp o haidAu m4ch di€n u = l20cos (100 rt +nl4) V rhi dien 6p hai dAu tp di€n td: 1.u.= 120.{tcos(l007rt) V B.uc = 60Jtcos(t00zrt+ r/?) y C. uc = 120 cos (100 rt ) V f). uc = 120 cos (100 7rr - nl4) y Cffu ll: Trong m6t thinghi€m giao thoa tr€n mdt nuoc, hai ngu6n krit hop S; vd 52 dao cl6ng cirng pha voi tAn sd f = l5Hz. VAn t5c truyAn s6ng trdn mdt nudc ld 30 cm/s. Goi d1 vd d2 lAn luol la khodng ciich tir di6m dang xdt d6n Sr vd Sz. Tai di6m ndo sau cl6y dao d6ng s€ co bign dd cuc dai B. dr = 24 cm d2 = 2l cm. D.dr = 26 cm, d2:27 cm Ciu 12: MQt ngu6n dm S phdt ra mdt dm co cdng su6t P khdng d6i truy€n rling huong theo rnoi phuong. Tai di6m M c6ch S mgt do4n I m c6 mric cuong dq 6m ld 70 dB. Gid sir m6i truo.ng kh6ng hdp thu am, Mric cudng dQ dm t4i ditim N cilch ngu6n s m6t doan t0 m la: A. 30 dB B. 40 dB c. 50 dB D. 60 dB Ciu 13: Mdt cloan mach xoay chi6u gdm dign tro R = I 00 C) cudn dAy thuAn cim c6 dQ ru cdm | = l/ r (H). Biiit tin s6 ctia dong diQn trong mach ld 50 Hz. tctlt tuqn ndo sau rt6y la dring v€ su l€ch pha giira diQn rip hai dAu doan mach (u) vd cudng dQ dong di€n qua mqch (i) A. Phacua u nhanh hon phac0a im6t gocxl4 B. Phacua u chdm hon phacua im6t gocnl4. C. Pha cua u nhanh hon pha cria i m6t goc nlL. D. Pha cta u chdm hon pha crla i m6t goc n 12. CAU l4: Nguoi ta goi d6ng co khdng d6ng b6 ba pha vi A. Pha cua ba dong di6n trong ba cuQn diy ld khiic nhau B. Ba cu6n ddy trong tlsng co khdng gidng nhau. C. Toc d0 quay cua r6to khdng bing tdc clo quay cua tu trrrrlrng quay +f: D. Dong di€n rrong ba cudn dAy kh6ng cuc dai cing m6t lfic, Ciu 15: Cudn so c6p cua mriy birin th6 c6 Nr :2200 vong m6c vdo mang di€n llOV. DC c6 th€ thip sring binh thuong b6ng ddn 3v rhi s6 vong crra cu6n tht cap phdi rd A.80 8.60 c.45 D. s0 cf,u l5: cho mach dj.T g?t ba phin tu mic n6i titip: R : 80e; cu6n diy cam thudn co h€ s6 tu cdm L vd tu di€n cd didn dung C- - r Y" vsrr !sr' Lrru Di€n rip tuc thoigi&a hai dAu doan mach u ='l60cos(100 rt) (v). Biiit culng dd dong di6n sc.nr ;,,,,. hon di€n rip u ld n/4 rad.Khi d6 titiu it *. cua cuong dQ dong di€n trong mach A,i= J-2cos(t00rt +x/2)(A). g. i: Jtcos(t00zrt _ |Tt4l(A). 9:i :?J?:yttt}}y:,n/o) (A).^ D i =.J2cosqt00n + n/4) (A). cau r7: M6t doan r.1"! qg* mQt rr.ign tlo ttrfl g: r1,i'*o vdi m6t tu dien. ei6t oicn 6p hi€u dung d hai dAu mgch ld 50-v, d trai oau aign tro ld 30v'Ei€n ip hi€u dung o hai diu tu di€n ld: A.20V 8.40V C.ZyJtv ; a - "-' v*i D.80 V Ciu l8: Phdt bi€u ndo ti sai khi n6i v€ dao dQng;id;;"; c0a vdt ? A. T6c dd crla v6r c6 grri tri cuc dai khi n6 qua vi trf cdn bing. B. Luc hOi phuc tiic dung l€n vdt lu6n hudng vd vi tr( c6n bing. C. Gia t5c cria v6t c6 gi6 tri dg lon cuc dai o vi trf bi6n. D. Co ning c0a vdt bi6n thi€n theo thoi gian. cau t9: Dd thi bi€u diEn su bi6n thi€n c0a gia t6c theo li d6 trong dao d6ng di€u hoa c6 hinh dang ndo sau cl6y? A. Doan thing B. Erong thing C. Duong tron D. Duong parabol ciu 20: cho mach dao ddng di6n tu g6m m6t tg Q : 5 pF vd m6t cu6n ddy thudn ciim L: 50 rnH. Sau khi kich thich cho mach dao ddng, thdy hi€u di€n th€ cuc dai rr€n ru di6n dar gi:i rr! 6v. Khi hi6u diQn rh6 tric thoi tr6n tu di6n rA 4V thi cuong d6 ddng cti€n i qua cu6n ddy ra A.i:3f.ro-,n B. i:2.'6.t0-,e C. i= 2.lo-2A D. i: Jl . to-'t ciu 2l: Phrit biiiu ndo dudiddy kh6ng ttring khi n6i vd ndng luong trong mach dao d6ng LC? A' Ning luong cia mach dao dQng gOm cd ning luong didn trudng tdp trung o tu cli€n vd ning lucrng tir trudng t6p trung o cuOn cAm. - B' Khi ndng luong di6n truong trong tu gidm thi ndng lucrng tu truong trong cudn cdrn ting l€n. c Ndng lu<rng di€n trudng vd nrng luo-ng tir truong cirng bri€n thi€n didu hoa vd.i tan s6 cua dong di€n xoay chidu trong mach. D. Tai moi th'i di6m, t6ng n6ng rugng di€n truong vd n6ng ruong tu rruong rd khdng d6i. Ciu 22: BAn ch5t 6nh siing c6 rinh ch6t s6ng rluo. c chrimg to boi: 1 ]tj:r tu'o-ng giao thoa. B. hign rugng quang phiit quang c' hi6u tugng quang diQn' D' hi€n tuqng phrit-eiectron do nung n6ng. cau 23: Trong thi nghiQm giao.thoa. hai khe"ioung krroang ciich gifta hai khe srsz :O,gmm. Khoing cdch tu hai khe e6n rnan anh la D : 1,2 (r). ilg;l;l'phrit rinh s6ng don sic co buoc song 2' = 0,75pm- Tr€n mdn dnh rdy di6m M cdch v6n trung t6m 4,5rnm thi di6m M thu6c A. vdn toi bac 4 B. v6n s6ng bdc 4 Cl vdn,ai,r,,,, j"'s'v"I Iy'| "'H.'u^n sdng b6c 5 [...]... g6c vo'i rnat phdrrg dia til trang thiii ng.lii sar"t 4 gi6y thi quay du'o-c vong dAu tien Mdmen qudn tirrlr (i)cLta dla tron na)/ la' R"l=0.6kg.rn2 Cflu 54: VAt rin B l:6kg.m2 Cl I= l,2kg.m2 I) 1:: 0.l2kg.rrr2 tinii I thi quay quanh m6t truc c6 dinh c6 m6nren cldrrg [uong I-, va Irdnrerr cludtt cl6ng nbng quay Id: D.2t lt.: B L1 l2l C, L2 2I A Lt 2t Cflu 55: Trong thi nglri6m Y-dng vd hi6n trrong giao... hi€u dung tr€n hai biin tLr dien lut)n ld cho rnach rrr6t cdng sudt ld: clr-r1'11i ,i't,, 5V thi phiii cung c6p c 1250w l) l2.50mW B 625W A.62,5.10-6 W CAu 40: M6t con lic ld xo treo thing dilng Biet d6 cung cria lo xo lii 20N/nr vd kh6i ILlong c'.tia vit tleo ldr 100g LAy g : 9,8rn/s' K"o vAt theo phu'ong thing dilng *u0ng dLl6'i ldnr clro li) xo gi,lrr 6.9cm r6i bL'6ng nhe ra d€ vQt clao tl6ng didu... bang rrhait va bang n/40(s) thi dQng nang cLia vAr co gi6 tri bang thc nlng cria lo xo NEu bie; d6 dao ddng ld 2 crn thita c6 phu'ong trinh dao d6ng cua vdt nhu sau: A x: 2 cos (20t) (cnr) B x:2 cos (401) (cm) C x: 2 cos (801) (cm) D, x = 2 cos (l0t ) (cm) 2: Khi chi(iu lAn lu'ot vdo cat5t cta m6t tC bao quang di€n lrai b0'c xa co bu.6'c s6ng ld Cfiu )r=0.2pn vd \=A,4pnt thi th6yvAnt5cbarrdAucucdai... Ndu cuong dQ ddng di€n hi€u dqng qua cu6n d6y rit 4,4 Athi ;e sa blng: 9:lt it ;6;;;;; A.0,5 B t/\6 c.0,2 D 0,8 cflu39:Ndngluongri€nkdtcriahat -rit2B,4Mev,cuahat vfng hon hat a ld do: A Hat nhdn c6 sO ttr6icdng lon rhi cing b6n vfng iiNa rd r86,6Mev.Har iiNa b€n I* B Hat nhdn nio c6 ntrng rugng li€n ktit n*,r tni u,cn v0ng hon k6t ri€ng cdng ron thi cang fcn vrrng c I{at nhdn c6 rring ruong ri€n D a... cdng ron thi cang fcn vrrng c I{at nhdn c6 rring ruong ri€n D a ld d6ng vi phdng x4 cdn iiU ciu td d6ng bi b€n 40 Trong 8 hdnh tinh xa Mar Trdi thi hdnh tinh xa A Mdc tinh B rh6 tinh Mit Troi a Hil v;;;;; nhat ld: D rhi€n Vuong rinh rr PI{AN RIENG (lo cAu Thi sinh chi tluEc lim mQt trong hai phAn (phin A holc B) 1-fh!! :chuong trinh Chudn e0 c6u,-.tdr cai tt itdn cAu Shj Ciu 4l Chon cdu rri loisai... rAt nhe ntru Hidrb, Hef ifcilt hqp lai v6iihau la phan:.rlng nhi6t hach D Phan ri'ng nhiot hach tod ndng ruong r6n piran *ng phan hach ban h; ciu 42: 'DAu A cia mQt soi ddy ddn hdi cdng thing, nim ngang iluoc kich thich cho dao d6ng diiu hoa vdj tAn sti 50 Hz coi ring soi ddy r6t oai vpn t6c truydn s6ng tr6n d6y bing l0 m/s Nh*ng di6m dao dgng cr)ng pha, nguoc pha v6i A, c6ch A nhirng A dr = l0k (cm)... (8nt + r/3) (crn) D.'x:4 J7 sin (8rt + n/3) (cm) CAU 45: Mdt mgch dao tl6ng ttiQn tu di€u hod LC vdi L = 0,lH vd tu di€n c6 cli€n dung C = l0pF Tai thoi di6m cudng dQ ddng di6n trong mach lA 30mA thi hieu diQn thi! gi*a hai bdn tr,r diQn ld 4V Cuong dd ddng dign cpc dai trong khung ld A.40 mA B 50 mA C.60 mA D.80 mA CAU 46 : Mach dao tlQng di€n tir ri€ng v6i cu6n ddy thuin cim c6 hQ s5 tu cdm ld L = 3mH... 608 cnu f: I PhQn chung tu cdu t o6n h6t cdu 40 d|ty ld phAn bit buoc O6i voi moi thi sinh 2 Phdn ri€ng: Chi chqn mQt trong.hai phAn A hodc B Ndu ldm cA hai phAn coi nhu pham quy vd khdng ch6m di€m phAn ri€ng E'I{IJNG'E'AI\4 !3$T i}TT#NG VAi\ FIGA T'ruANG T,{}NG KV T.E{[J'LAN TxdLI,{}3 T'F{T na0m:vAF[,y Ng*y 'I'hd'i thi: gian: \3161201fi 90 phrit Dd biti g6m {)6 tang I PIIAN CIIUNG CI{O T'A't Ca rui... m6t r6nh nho Bi6t chu ki dao d6ng ri6ng cta khung xe tr€n cilc lo xo gidm xoc ld 1,5 s Tdc d6 xe bang bao nhi6u thi xe bi xoc manh nh6t? A 54 km/h 8.27 kmlh C 34 km/h D 36 km/h CAlu26:Trongphdntrng iA+iA +iAe+n,n€undngluongli€nk6tc0ac6chatnhdn iA.in va tdn luqt ld a, b vi c (tfnh ra MeV )thi ning lugng duoc gidi ph6ng rrong phdn ring d6 (tinh ra iUe MeV ) la A.a+b+c B.a+b-c C.c-b:a D.c+a_b Ciu27: N6u... di€n tir:h cu'c dai tr€ti 1Lt di0n ld l0-7Clvd cuo'ng dO cuc da.i cira ddng cli6n trong cudn ctirn lA lA Ilutlc scing md triaclt tt;tt' cothr5b6tdu'ocld2.ThaytUCbingtu C 'thi bu'o'csongnramachthudrto'clit2A.N€Lr nrdc('rir C'rr6i ti6p thi mach bit dtro-c s6ng c6 bu'ti'c s6rrg ld: D l6,85rn C l68.5rn B.2l,06rn A.210,6m Tai noi c6 gia t6c trong trud'ng ld g, m6t con lic clon dao d6ng nho clidu hi)a xung . thi n theo thoi gian. cau t9: Dd thi bi€u diEn su bi6n thi n c0a gia t6c theo li d6 trong dao d6ng di€u hoa c6 hinh dang ndo sau cl6y? A. Doan thing B. Erong thing. SaLr khi kich thich cho h6 dao d6ng, didn 7' tfehbi6'thid'rheoquylLrar q=z,5cos(2-,103nt)(rrc).cu6ndaycdd6tucdrnbang c. L: I H E ciu26: Trong thi nghi6m Y-dng. hod v6.i tAn sti g6c , = JTC' B. Ei6n tich bitin thi n theo lrdnr s6 mfr rheo rh6.i gian C. DiQn tich bi6n thi n tLrAn hodLn theo tAn s6 g6c ol. .i " D. Ei€n