THI LÝ L5 2011(KHTN HN)

Trong sdng diQn tir thi dao dQng c&a diQn truang vd tr.r truong tai mQt di6m lu6n d6ng pha vdi nhau.. S6ng diQn tt lan truydn duo-c trong chdn kh6ng vd mang n6ng luong.. Tiong s6ng diQn

e e e Thdi gian ldm bdi: 90 philr,

Chobi€t: hangsOPlangh:6,625.10-14 J,s; d0 l6ndi6ntichnguy€ntOe:1,6.10-'eC;

t6c d0 6nh s6ng trong chdn khdng c : 3 I 08 m/s.

I PHAN cHUNc cF{o TAT cA rgf sIMl (40 cAu, til.c6u I d6n ciu 40)

C6u t: Miu sic tr€n bong b6ng xii phong dugc t4o thinh ld do hi€n tugng:

A Tdn sic rinh sring B Giao thoa dnh sdng C Nhi6u x4 iinh siing D.

Cdu 2: Trong m6y quang pfrO tang kfnh 6ng chuAq trgc c6 tiic dr;ng

A Tao ra chtrm tia song song cira cdc c6c tia s6ng chi6u vdro ldre hep F d mQt dAu cua 6ng

B Phdn tich chim tia chi6u vdo 6ng thdnh nhiAu chirng tia don s6c song song

C HQi tU c6c chum tia song song don sdc thinh c6c vpch dcrn sic trdn kfnh K cria 6ng

E+i r,{Qc nG{oA HQA Tu NTrrtN

TRdId\TG T.FLPT' CHUYEN KHT.N

di€n frd la:

A.200 w

C6u 6: X6c dinh h4t nhAn X trong phrln u'ng h4t nh6n sau: p +7 Be -+ A + X

t r-/

J 2t',

EE TI{I T'E{{.IEAI rjqc X-AN 5-NAM rrOC 2010 - 20X1

MON THI: VAT LY

c.50 w.

C J" LT.

B PhOtOn, lepton, nuclon

D Phdt6n, lepton, barion

B, x: -? cm; v: -0,2n mls

D.x:+2cm; v=-0,2nmls.

Me de rhi

134

Khfic x4 rinh siing

D.3m

l00sin(cot) V C0ng sudt tda nhift trdn

D 100 ui

a

D 2tle.

D T4o ra quang ph6 chuAn cira ngu6n S.

Ciu 3: S6ng di6n tri kh6ng cd tinh ch6t niro sau ddy ?

A Trong sdng diQn tir thi dao dQng c&a diQn truang vd tr.r truong tai mQt di6m lu6n d6ng pha vdi nhau

B S6ng di€n fi Id s6ng ngang

C S6ng diQn tt lan truydn duo-c trong chdn kh6ng vd mang n6ng luong

D Tiong s6ng diQn tir thi dao dQng cria dign truong vi ttu truong t?i mQt di€m l€ch pha nl2

Cdu 4: Co thO nguoi b4n ld ngu6n phdt tia h6ng ngo4i c6 budc s6ng

CAu 5: HiQu di6n thti xoay chiAu giira hai dAu dign trd thuAn R = 100O c6 bi€u thric: u =

B 150 W

*

t'"

{r

.,n

CAu 7: C6 thd phAn lo4i h4t so cAp thdnh

A Phdt6n, lepton, hiperon

C, Phdt6n, lepton, hadron

a o ,d.-l =j

1

L

=-44

Cdu 8: Xdt con lic dao d6ng diAu hda vdi tin sd g6c dao dQng ld co: i0n rad/s Tai thoi di€m t = 0 I s, v4t nim tai li d0 x ='-2

cm vii van t6c co d0 lsn0,2T m/s hudrg v€ phia vi tri cdn bing Hdi tqi thoi di6m t = 0,05 s, vdt dang d li dQ vd c6 v4n tOc bing

bao nhi€u?

A x = +2 cnr; v = +O,?rc mls,

C, x= -2 cm; v = +0,2r m/s.

CAu.9: Chi6u vdo h€ giao thoa hai khq Young chirm 6nh s6ng tring c6 budc s6ng thay AO; tl€n tuc ru 0,40 pm d6n 0,76 pm T4i

vi trivins6ngb4c4ciadnhs6ngd6 (7,:0,76prm)cdnc6mAybricxanfrachocucdaigiaothoa?

CAu l0: OOivOimot hieu di€n thtl xoay chi6u thitrong m6i chu ki,T0, thbi gian nid hieu digri th€ tfc thoi c6 giri tri l6n hcrn hiQu ,,^ , L.^

di0n thd hi€u dqng cia n6 ld

T-ail

D I -= lt

^uL

Cdu 1l: Xdc dlnh n6ng lusng toi ttiicu cia c6c phoron ^1d6 thuc hi6n phdn img sau: ? C * y -$(lHe) cn" bii5t: m(Cl2)

= l2u; m(He4) = 4,0026a;h = 6,625.10-t'Jr; , = 3.108 m/s

Ciu 12: R6to crja mQt m6y ph6t diOn xoay chidu mQt pha quay voi t6c d6 900 vong/phirt c6 4 cilp clrc Bic Nam s€ t4o ra dor'g

, l , t A

olen xoay cnleu co ian so:

CAu 13: M4ch di€n xoay chiAu kh6ng ph6n nh6nh gOm lAn luqt ba phAn tri: di€n rd thuAn R = l0 O, cudn cdm c6 di€n trd r = 2 fJ

vi d0 tU cirm L = 0,2n H, tg diQn c6 di€n dung ld C = l0-3ir P Mic vdo hai dAu m4ch mQt higu diQn thi5 xoay chidu co gi6 tri hi€u dr,rng U = i20 V vi.tAn sd f ttray AOi dusc V6n kti mac vdo hai dAu do4n m4ch g6rn cuQn cdm vdtlt diQn sE chi

n Uieu diQn th€ nhd nhdt la 20 V ts Hisu dipn th€ khong d6i le 120 V

C HiQu dign thd lcrn nhar ia 20 V D, HiQu di€n th6 tdng l€n khi tsng tAn s6 f

CAu 14: M4ch rliQn xoay ehiAu kh6ng pbdn nh6nh g6m diQn trd thuin R, cu6n c6m thuAn c6 c?rm khiing Zsvittr1 dign c6 dung klrdng 2 = ZZy.Yito mOt thdi di€m khi hieu dign thii tr€n diQn trd v?i trdn tq diQn c6 gi6 tri tric thdi tuong ung ld 40 V vd 30 V thi hipu diqn thd t0'c thsi hai dAu mAch diQn ld

Ciu i5: 'l'r€n ssi d6y hai diu cti dinh, chidu ddi 1,2m xu6t hiQn s6ng dirng co 4 nft s6ng (k€ cA hai nrlt d hai diu) Di€u ndo sau ddy sui?

Tnngll4 - Ma dd thi 134

A- Buoc sdng Jd 0,8 m.

9.9-?" didm nim gifta hai n[t li€n ti€p dao dQng cirng pha

! {hoang ciich gi&a mQt nft vd m6t tung c4nh n6 tj O,g m

D Cdc didm ndrn d hai b€n m6t nLlt dao d6ng ngugc pha

Ciu l6: Chon cdu sai

A' Quang di€n t.d vd pin quang di€n ho4t dQng dua vdo

hiQn tuong quang di€n trong

B Laze bdn dAn ho4t d6ng dua vdo hiQn tuqng-quang di€n trong * ' '

!' L6 trong vd electron d5"n

""rgll.* gi afi oier trong chat quane ddn

D Nhi€u chdt quang d5n c6 gidi h4n quang ddn nim trong virng h6rig ngoai.

CAu 17: Tirn ph6t bi€u dring v6 phdn *ng ph6n h'ach vd phdn *'g nhiQt hach:

A Cd hai lo4i phdn rlng h.6n d€u tda n6ng lugng

B PhAn rng nhiQr ha.-lr 06 xdy ra hoa phln ung ph6n hach

C Ning lugng cia m5i phan ung nhi€t hach lon-hcrn phdn ring phdn h4ch

D MOt phdri ri'ng thu ndng lugng, mQt phdn ring toa n-dng luong

Cdu 18: Hai didm M, N nim trong midn giao ihoa ndm crich cdc ngu6n s6ng nhfrng do4n bing d1y : l0 cm; d2s = 35 cm; vd d1x

:30 cm; d2x = 20 cm' cac nguOn phrit s6ng d6ng pha vdi

budc s6ng I = 3 lm Tr€-n duong

"3i rt,1i.r cd bao nhl€u di6m dao dQng

vdi bi6n d6 cuc dai?

A 10.

Cdu l9: Tim phrir bi€u sai

D cd d0 lon c$cti6u

Quang ph6 vach phdt xa crla cdc ctrAt khac nhau thi khdc nhau v6:

A Mdu sdc cdc v4ch ph6 B 56 luqng cdc vpch ph6.

C DQ sdng t! d6i gifra cdc vach ph6 D 86 rgng"c6

"?;tp;;:

Ciu 20: S6ng dign hr c6 tAn s6 tOtr4Hz nim trong virng ddi s6ng niro:

A S6ng trung B S6ng ddi -c song ngin D S6ng cr,rc ng6n

cau 21: Chon cdu phrit bi6u sai khi n6i v€ dao d6ng ri€ng kh6ng tdt dAn trong mach dao d6ng

A' Ndng luong cia mach ddo dQng ri6ng gdm ning lugng diln Fuong t6p trung d ru di€n vd nang lugng fu truong tflp trung d

cu6n cdrn

B' Nang luqng cria mach dao dong ri6ng t4i m5i thoi di€m d€u bing n6ng luong di€n tru,ong cuc c4i hoflc ndng lug'rg tir truong cgc dai

I Iai moi thoi di6m, ndng luqng cria m4ch dao d6ng ri€ng d€u bSng nhau.

D' Trong que trinh dac d6ng ri6ng, n5'ng luong diQn trumrg giarn bao'nhieu lAn thi nang luong tir truong tLng dfng b6y nhi€u ldn.

CAu 22: Dd thu duoc sdng di€n tu c6 buoc s6ng 2' : 300 m, ta cAn dirng mach dao dQng

LC g6m tu diQn c6 di6n dung c = l0 pF

vd cu6n cirm c6 d6 tu cdm bing bao nhi€u? L6y n2: 10.

9it ,?1' Dat hi€u di€n thti u : Uesin(ot) vdo hai ban ts diQn c thi cuong rid dong di€n

xoay chi6u trong m4ch sd bi6n d6i theo bi€u thric:

CAU 24:- Khi mQt v4t dao dQng di€u hda thi vdcts v6n t6c:

A lu0n OOi ctrieu khi di qua g6c toa d6

B ludn cing chi€u vOi vJcto gia tOc '

C lu6n aOi ch;Au tctri vf,t chuyln dOng d€n vi rri b;en

D lu6n ngugc chi6u vdi vdcto gia iOcl

Ciu 25: Mdt v6t dao dOng diAu hoa theo phuong trinh: x = 2cos(2trt+ n/6) (cm); trong dd t dugc tfnh theo don vi gi6y G) D6ng

ndng cria v6t vdo thoi di€m t : 0,5 s

A i = %Ca;sin[ *, -;

) c.i=%rin( Ca \ tj ,t-o\ D

rt / -\

i = I-Q-rin]1t + lL I

cr-_(*"'2)

i =(JoCotsinl a:t + " I

A dang t6ng I€n B c6 d0 lon cgc d4i C dang gidm di

Chu 26; Dao dQag duy rri ld dao dQng mii ngudi ta dd:

A Ldm mit lgc cdn crla m6i trudne

B T6c dung ngogi luc bitin doi tuyEn tfnh theo thsi eian vao vdt dao d6np

C Kich.thich lai dao d6ng sau khi dao dQng oa uitiihin - -:"or

D TruyAn ndng luong chi vdt dao d6ng itre"o nrQt quy ludt phir hqp.

c6'u27:cdcmricndngluongctanguy€ntriHidro lit: Er #Gr),vdin:1,2,3 rusngrmgv6icdcqu!d4odirng

n crla electron' Khi electron chuydn ru qu! d4o N v€ qu! dao L thi nguy€n tt ph6t ra vach ph6 c6 budc s6ng

c6u 28: Con i6c lo xo rhing <irlLng g6m vat.kh6i luo.ng m = 200,g lreo vdo lo xo d0 cimg k : 100 N/m' cho vdt dao ciong theo

;;"";;'rhA"c ;;"; "; uien?O a1"+ cm LAy e: t d ,ils' Do bi6; dang cqc dai cua lo xo trong que trinh dao dQng ld:

A' 4 cm B 6 cln' C' 8 cm' D' 2 cm'

CAu 29: MQ! photon cria 6nh sdng miru 1'dng (i" = 600 nm) cd ndng luo'ng tinh theo o'on vi eV bing:

Cdu 30: Diiu nio sau dAy kh6ng phn 66p

'oi thuy6t lugng tri 6nh sdng?

A C6c hat dnh s6ng li nhiLng phdtdn bay vo"i t6c d0 l<hdng d6i 3 ' I 0" m/s'

S VOi *6i anh san! don sic-, cac phOtOn diu gi6ng nhau'

C Phdt6n chi tdn tai trong trang th6i chuy6n dQng'

p tr45i tAn nguy0n tir ph6i xa ann sang thi n6 ph6t;a mQt ph6tdn'

C6u 3l : MQt dao d6ng ld t6ng hoo cua hai dao dQng diAu hda t1".Ct^htr.*q cung tAn s0 c6 d0 lqch pha ld 900' Bi€t ring v?ro mqt

thdi di€m thi ti do cira cdrc dao dQng thdnh ph6n ta 6;m vd 8 cm lido cira auo o6ng t6ng ho.p vao thdi di€rn Av bing

C6u 32: O6 tni cria dai luo.ng X phU thuQc vdo d4i lugrg Y ndo dudi-ddy se ld dusng thing?

A X le nEng luong cira p-nOtOn con Y lir buoc s6ng cria bric xa di€n tu'

B X ld dQng nangldn i ta uan t6c cua electron quang diQn'

C X la nan'[ tuo.ng ct a pt Ot6n cdn Y ld tAn s5 9ql Unc xa di€n.tir t"*g 1"q: ^ A

D X le b6n kinh quy eei dtr.ng ciia nguy.n tri hidr6 cdn Y ld c6c s6 nguy€n li6n ti€p

c6u 33: phuung trinh daoaong c,ra aidm rr,1 nim tr€n phuong truyAn s6ng, crich ngudn s6ng mQt do4n bing x: (57'/a) ivdi i ld budc s6ng) lir: upl :4cos(2nt + r/3) cm Coi bien d; t;;; il;;g Jair.n'i t iyAt ai, ulet pnu*g trinh dao dQng cia nluon s6ng'

A u:4cos(2nt + 5nl6) cm B u = 4cos(2nt - z/6) cm'

C u = 4cos(2n t -2113) cm D u = 4cos(2zrt + n/3) cm'

Ciu 34: Trong phin img hat nhdn, dai lugng ndo sau ddy dugc b:o-l?11',

Cdu 35: Chgn cdu dtng

MQt irong nhtng uu di€m cta mriy bi6n thii trong sri drlng li:

A Kh0ng bric xa s6ng diQn tti

B Kh6ng ti€u thr,r diQn ndng

C CO tnE t4o ra c6c hiQu diqn thO theo y€u cdu sri dqng'

D Kh6ng c6 su hao phi nhi€t do dong diQn Phuc6'

tri cdn bing co t.c d0 ntru CAu 36: cnl nai con l6c don dao dOng di€u hba t4i cirng m6t vi ri dia.19.,Hai quir n[ng khi di qua vi

nhau Bi€t chi€u dai aav # "i1""" ii" ,i"

"1,ar 1.o uien d6 g6c cr1) dai gAp dOi con lic thri hai (c6 bi€n dQ g6c cx2)' Ta c6 l; * ^ ^ _ a,- n /."

CAu 3T: MQt chAt ph6ng x4 cu 1 ngdy thi gidm di 10% lusng chft ph6ng x4 ban diu' Chu k! b6n rZ c.ia chdt d6 bing:

I r J rrsFj r

Cdu 38: fa gqi d$ng co sri dr,rng til truong quay ld l<h6ng ddng b0 vi:

A R0to quay khdng dAu khi nhanh khi ch4m'

g nOto quay vOi tAn sO nh6 hon tAn s6 quuy cria tiL trr-ibrg'

C nOto iuay vOi tin sd lOn hcrn tin sO quay cta tij trudng'

D ROto quay ngugc chiAu quay cira tir tru0ng'

CAu 39: D6 rn6c cuong dQ .t u rong 6m thay d6i tir 20dB len 40d8, ihi.cuong dQ drn cria s6n8' dm Phai tanB:

CAu 40: Mic viLo do4n rn4ch RLC kh.ng phAn nh6nh mQt ngudn diQn xoay,chi€u c6 tAn sO tl.'ay dOi du-oc' O tAn s0 fr :60 Hz' he s0 c6ng su6t dpt ,iu ,ri "0 iui;;;."dr;a" J;= il;;:;; 't;o"e r"'i, nhfn gi,i tri costp 0,70't' o tan sri f: = e0 Hz' he s6 c6ng suAt cira m4ch b6ng:

L.o,stz B' 0'486 c.0,625. D 0,781

II FHAN RITNG [10 czul

Thi sinlr chi tltqc ldm ntQr troyg hai phin (phin A Ito.Erc B)

A Theo chuong trinh Chu6n' (10 cfru, ri'cdu 4l din cdu 50)

cau 41: Tai thd.i 6i€m ban tiau (t: 0), vat dao.d6ng di6u !tr-a crruril d6ng qua vi trf x = 2cm ra xa vi tri c6n bing vdi t6c dQ 2c r*1, et6i ttu ty i u dao dQng i : O,OzS s' Vi6t phuong trinh dao dQng cria vft:

A x=zJi"o|,ro,*7\r* B' x=2Ocosl

'o'*!lcm'

c x =z^,[i"or(to, -'- -L'|.r* D' rc = zJz cos[ t'1' -'-: lcm'

Ciu 4l;Trong d$ngco k-h6ng ddng bO !1 phu:.lt truong quay quay.voit6c dQ

goc:

A Nh6 hcrn tdn ,6 g6;';fi.;;"-g d'O dong diQn - g' eicn a6i diAu hda theo thdi gian'

C Bang tAn s0 g6c cira cubng dd ddng diQn D' Lon hon tAn s6 g6c cria cuong dQ ddng diQn'

TranP3l4 - Ma dA thi 134

C6u 43: Khi s6ng 6ni di tir n6i trucrng kh6ng khf vdo rn6i truo.ng rin:

4 Bi€n d0 s6ng tdng l€n

C NEng luolg s6ng tdng l€n

ts TAn sO s6ng tang l€n

D Buoc song tdng l€n

C6.u 44: Dao ddng cta con ldc trong dOng h6 qud lZc ld dao d6ng thuQc loai:

A Dao d6ng tu do

C Dao dQng t6t d6n

Ciu 45: Trong m4ch xoay chiAu RLC mac n6i

kh6ng thi

A 1,32 eV B 1,69 eV

C6.u 47: L6 den

A Quan s6t thdy F€n bA mdt Mer Troi

C PhAt ra buc x4 kh6ng nhin th6y

A hieu di€n th€ trdn di€n tr6.R bing 0 con rrdn hai phdn tu c6n lAi khdc kh6ng

B hi6u di€n thti trOn di€n trd R vd rr€n cuQn cdrh.L bing 0 con rr€n tu di€n C inl thac 111rong.

C hiQu di€n th€ trdn cir ba phAn ni R, L, C d€u bang kh6ng

D hiQu diQn thti tr€n diQn tio R va tr€n tq c bing 0ion tr€n cu6n cdm L khiic kh6ng

Chu 46: Mdt chAt c6 gi6i h4n quang dipn bing I 8 8 nm Ch6t d6 ci.c_6ng thorit bdng:

B Dao dQng cu0ng bti.c.

D Dao d6ng duy tri

titip (cuOn ddy L thudn cdrm), viro thoi dicm cucrng d6 ddng diQn trong mach bing

B Cd mdu den

D Cd fruong h6p ddn rit m4nh

Cdu 48: MOt chAt phdng x4 c6 chu k! bdn rd ld T = 8 gid Sau 1 ngdy d€m, t! s6 gin'a s6 h4t nhdn chft phong x4 con l*i va si5 h4t

nh6n dd bi phdn rd thdnh chit kh6c ld:

Ciy ol:^Chg hai mSch dao dQng litudng LC c6 cirng tAn sd dao dOng ri€ng f6 Ntiu mic hai m4ch niry n6i Uep v6i nhau thi mach mol cd tan s0 dao dQng ri€ng ld f So s6nh fvd fs.

Ciu 50: Ciic vqch meu trong ving iinh s6ng nhin thAy cira quang ph6 vach phiit xa cria Hidr6 cd miiu

A D6, cam, lam, tim

C Dd, vdng, chim, tfm

B t/7

B l6 rad/s

nhanh dAn quanh nr6t truc c6 dinh

B Theo chuong trinh Ndng cao (10 crtu, tir cfru SI d€n cfru 60)

-C:u,s], f CYqiri }1c dinh t6c d6 cia.mdt ngu6n Am b6ng c6ch sri dsng thi.:t bi do tAn so am rchi ngudn dm chuydn dQng thang

d "

iiigi" thi€r b!.dangdrnrgy€n thi tniet bi.do dugc tAn so am la724Hz,con khi ngu6n dm chuyZn dQng rhing aeu'ufil .Jng

t33 0O qo ra.xa.thiclt bi thi thiOt bi do duoc tAn.sti 6m.ld 606 Hz Bict ngu6n dm vd-rhiilt bi tu6n .tn! n'i,n

"?n n,0, a"*g

thdng, tdn s6 cia ngu6n dm phdt ra ld khdng doi va toc d6 truy6n drn rJng m6i truong bing 338 mls.ioc aO.,ia ngu6n am ndy Id

B Dd, iatn, chim, tim

D E6, cam, viing, tim

lUc M = 5 Nm lOn vdt c6 momen qu6n tinh I : 20 kgm2 thi sau thdi gian At:4s, t6c d6 gdc cria vdt

A.v:35rr/s.

Cdu 52: Tdc dpng m6men

thay ddi mdt luong bing:

A.25 radls

Cf;u 53: Xer vAt rin quan.

di0rn narn tr'€n vdt:

A Khong doi

C Tdng gAp bOn lAn.

I2

1^r

C I rad/s D 8 radls

Khi t6c d0 g6c c0a v4t tdng g6p d6i thi gia t6c todn phAn cia m6t

B Tang nhtrng cliua rdi b6n lAn.

D Gidm di bdn lAn

c0u 54: MOt chAt huj,nh quang m?ru xanh lam c6 thii hdp thu dugc bric x4 miu ndro sau day:

cAu 55: M9t hat c6 dQngndng bing l/4 nang Iuong nghi cta n6 T6c d0 crla hat d6 bing:

CAu 56: Khodng thdi gian ngin nhAt d€ vdt dao dOng di€u hoa chuy6n dQng tir Iy d6 x : -Al2 diin x : A/2 ld:

Ciu 5.7:

Y9lJ.a, quay dOu quanh truc quay c5 dinh c6 mornen dQng luong L = l0 kgm2/s vd dong n6ng w6: l0 J Momen qudn tinh cila vdt d6i vdi truc quay ldr:

CAu 58: Thi€n thO nAo khOng thuQc he Mat Trqi:

A Mat Trang , 8 Sao ch5i C punxa O ThO tinh.

CAu 59: thothanh thing, d6ng chAt, chi€u ddi L vd kh6i luong m Momen quiin tinh cria thanh quanh truc vu6ng g6c vdi thanh

di qua di€m gif,'a cria thanh duoc tinh theo bi6u thuc ndo sau tldy:

o I =!*t]

4

C6u 50: Gi6 tri tfc thsi cira cuong dd dong dien vd diQn tfch tren-tu di€n cira m6t rnach dac d6ng LC lj,tudng tai cdc thdi di€m t;

vir t2 lAn

]:fl ,r,,,i, = 6mA; 9r = 4.iO-s C va l, = -8mA; 9: = 3.10-8C TAns6 goc crla dao dong di€n tir nong *"a.h ta,

ilAi HCC KHOA FXQ,C TnJ NHrcN

TrIUOING TFil'T CS{T]Y'6N KtrTT'N

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i-,gON T'E{{: VAT'i,V

CAU

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