de thi HSG vat ly NAM DINH 20082009

<span class='text_page_counter'>(1)</span><div class='page_container' data-page=1>

DE CHINH THLTC

* pnAx rn4c wcnfinr-[nicn outx ( z.o aiiimt

Ciu 1. Cho ddng di€n xoay chidu va dong di€n kh6ng OOi tan luot cha)'qua mot cuon dAv thi
^ 4 . . ^

cdng sudt ti€u thu cua doan mach nhu nhau. 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

A . l .

B. ^[t .

Ciu 2. Hai vAt rin A va B c6 .mdmen qu6n
dQng ndng quay cua A so v6'i B bang

so GrAo Dvc - DAo T4o

NAM EINH

Ciu 5. MOt con lic vdt ly ld rn6t thanh
ddi (. dao d0ng di0u hda xung quanh mdt

mornen qudn tfnh cua thanh d6i vcyi truc quay ld

KV'tHI Hoc sINH GIoI Tllpr roAN rixn

NAM HQC 2008 - 2009
Mdn : Vit ly Lop 12

(Thd'i gian Idm bdi 180 phfit, kh\ng kA thd'i giun gioo tlil
Di thi girr 02 trang

c . 2 .

_{D . U "lt .}

tinh Ia :Zls c6 momen d6ng lu'or-rg La : Ls. Ti so

A . 2 .

B . 4 .

( c.)t

t z .

_{D "{t}

\_--l

Cf,u 3. MQt mach dao d6ng diQn _{F li tuong LC co chu kj, dao dong dien tu' ri€ng le T. D0 lon}
diQn tfch tr€n ban tu diQn tai tho'i di€m ban dAu birng 112 dd lon diQn tich cr-Lc dai. Tho'i gian ngin
nhAt tu'lirc ban dAu d6n khi di6n tfch tr€n bAn tu di€n bang 0 la

A . T l 4 .

B . T t 3

_{r e .}

T ^ 2 .

D 1 - t 6 .

Cnq 4. Me't chAt diOm dao d6ng di€u hda tr€n tr-FOx vo'i bi€n dqt A va chu ky T. Quang du'o'ng
dai ntrdt rla vAt dao cione di drro-c trong thoi giar^rTl5 bang

A. A",[t.

8 . , 0 , , E .

@n

T

A^12

L . - ,

2

r \ . n r r l

diri mA,rh, dong chit. ti€t
truc c6 dinh nim ngang

di€n deu khoi Iu'qng m clrieu
va vudng goc vo'i thanh. Bi0t
t .

I= I m.('. Chu k'i dao d6ng cta con lac do lr)

1 J

D . T : n

Ciu 6. MOt vdt rin quay quanh m6t truc cO dinh co phuo'ng _{trinh g : - 2 - 5t - 2t2. Trong do e}
tfrrlr bdng rad; t tfnh bing giAy. G6c quay cua vAt trong tho'i gian t: 2 giAy ke tir lirc ban dAu barrg

6 . t 8 r a d . B . - 2 0 r a d . C . 1 6 ra d . D . 2 8 r a d .
CAu Z. Mgt ngu6n Arn ph6t ra rn6t 6m co bAn co tAn s6 f . I(hi guong dd 6rn

^ r r J t r \ r r v r 4 ^ ^ r ^

itn do bdne ben la L. T[ne cuons dd dm l€n 100 l6n thi rnu'c cudns d0 6m dcr

4 . 2 . L

B . 1 0 . L

c . L + 1 0

Cf,u 8. Hai con l6c do'n c6 cuns chidu dai scri d6v dao done di€u
goc crl : 2crz. N6u hai vAt nlng kTfmf.tq"g t"':-ZmzTht ;n*i

h o a o ' c u n q r n o t n o i v o ' i b i € n d o
d a o d o n g c u a 2 c o r r la c c o b i e u

7et

A . I : 7 t l - .

ls

0r-"

!3'

W

W

' ' /

-V g

r;

c r - 2 o l n

thu'c quan h€
( 4 . f , : T z .
\_/

la I thi m['c cu'ong do
blne ben la

( P L + 2

D . T r : T t l ' l i .

B . T r : 2 T 2 .

C . T r : t l i T z .

B. PruTN TU LI]AIV

,Brii

1. ( 4"0 di6m\ MOt thanh

AB dei manh

d6ng chdt,

ti6t di6n d6u c6 kh6i lu'orrg

_{m, -chi6u}

cldil,

q u a y q u a r r h , o o t _ t u u , ' o a i n n v u 6 n g g o c v o i t h a i h . e i e t m o m e n q , f f i n o T i ' - t ' *

1

</div>
<span class='text_page_counter'>(2)</span><div class='page_container' data-page=2>

l. .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 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 thanh. khAo s61 su'thay"doi 'r-rO r.n qua'
tfni-r cua thanh theo toa do 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 : 2 5 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 0. 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 6 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 6 ] f f i n g 5 0 c n r / s . B i € t k I l c r i i l r g

c 6 c h s i f r ' a h a i n s r r A n l i A R : 1 ) a n ' t

' _{- - - s - - - e} _{- 1}

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

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

2. LAy diern N tr€rt be rndt chAt long sao 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- 3 i

@

Hai

v'+t.Mr

ye M: 19 r<rrol

lue'n;',uo,r@

uu

I1l

non n1T ngalg sao cho truc cua lo xo luon thaqg

tltmg ( hinh l). Bo qua kh6i

.{l

o

o

lu'gng cua lo xo. ldr,v gia toc trong tru'o'nq/g:_O1li-l ' ' L _S _I

1 J - i , . l " J A l - . ; A . . r ^ ' - , - ^ ' " . ^ l : - ' ^ r l - i : f f i ] . l ( r ^ ^ F | +

I . Tfnh do bi€n dang cua lo xo L th-ne can bang? J ,5 }rn

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}

xudng.

gti--

toa do o rel

-v!,rri

cin bing cua M2. g5c rhoi gian-ld

lric rha v.. vier ihurmg rrinh tiao

d 6 n 3 r i r r l i ; t

_{X : - . < ( 4 2 0 L ) q r * . __ __}

^ . ] . T q b j : l { O j . r " d Q n g I 6 n n h A t c r : r a M . C i c h o M 1

l u 6 n l u t ) r r n i r n y € n i r o n g k h r M : d a o o o n g . r s , h ^

Brii 4. (6.0 ali€m) Cho mach di€n nhu hinh 2 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

/ r - - \ l

I u : 100 "12 cos I 00nt (V).\ |

. I A B

. ^ - ?

I t l t

-L C h o -L

TE 5n _{- / .}

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 khi cjo?

- , T t r ^ .

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 < 2
va LCco2 > 2.

Biii 5. (2,0 dj6-) Mgt mach p Sgrlg-,Aie"

tu' li' tu'ong LC gorn cuon day co do tu' capr

!;*|q+il.S

diqn

co di€n

aun\-r- 5 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 khi nang luo'ng dien tru'onglAp trung trJng tu Oier't t a"g

"a"-* f "n'r*ly.,ir.tr,rg
tap trung trong cudn chn-r? Trong khoang tho'i gian do 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 9 s}

l )

_{- ) A : C ,}

t , - l ,

u - L ' c

- ) L - ) r

*n Ur^

_{nd l)}

Lccr'<t

0"L

rk

Ho va t6n rhi sinh:

_Ctrfr'

_{ky cua giarn}

_{rtri so |}

_{,C.gp/: ,,i!.l. F- fr.^}

2--_1---L

l*c tt

</div>

<!--links-->