CHUN B RA THI CHN HSG CASIO VT L NM 2008 (D B)

yS GIO DC V O TO BNH PHC CHNH THCK THI CP TNH GII TON TRN

MY TNH CM TAY CASIO VINACAL.

NM HC 2012 2013

Mn: Vt l Lp 12 (Trung hc ph thng)

Thi gian: 120 pht (Khng k thi gian giao )

Ngy thi: 4/12/2012 Bui chiu

Chu y:

+ thi nay gm 05 trang, 06 bai, mi bai 5 im

+ Thi sinh lam bai trc tip vao ban thi nayim ton bi thiCc gim kho

(H tn v ch k)S phch

(Do Ch tch Hi ng thi ghi)

Bng sBng chGim kho 1:

Gim kho 2:

Quy nh:

+ Hc sinh trnh by vn tt cch gii, cng thc p dng, kt qu tnh ton vo trng lin k bi ton.

+ Cc kt qu tnh gn ng, nu khng c ch nh c th, c ngm nh chnh xc ti 4 ch s phn thp phn sau du phy.

+ S dng cc hng s ci t trong my tnh ton .

Bi 1: Chuyn ng ca mt vt l tng hp ca hai dao ng iu ha cng phng. Hai dao ng ny c phng trnh ln lt l v . Bin ca dao ng tng hp l 8 cm v tr pha so vi dao ng x1. Tnh A1 v A2.

+ n v tnh ca bin l centimt .

Cch giiKt qu

Vit c: .Tnh ng: ; .

.

.

Bi 2: Mt xilanh kn hai u c chia lm hai phn 1 v 2 bng nhau nh mt pittng cch nhit, mi phn c chiu di bng 50 cm. hai phn c cha mt khi lng kh nh nhau, nhit 270C v p sut 1 atm. Ngi ta nung nng kh phn 1 v thy xilanh dch chuyn i 3 cm. Tm nhit kh phn 1 v p sut kh khi .

+ n v tnh ca nhit l C v ca p sut l atm.

Cch giiKt qu

Trng thi ban u ca kh hai phn l: p0 = 1 atm; V0 = 50 S(cm3); T0 = 27+ 273 = 300 K. V kh phn 1 c nung nng nn pittng dch chuyn v pha phn 2. +Gi T l nhit ca kh phn 1 (sau khi c nung nng). Trng thi ca kh phn 1 by gi l : p; V1 = ( 50 + 3)S = 53 S ; T. +Trng thi kh ca phn 2 l: p; V2 = ( 50 - 3)S = 47 S ; T0 = 300 K. +p dng phng trnh trng thi cho kh phn 1 v phn 2:

= (1) v = (2)

T (1) v (2) : = T = To 338,29790 K hay t = 65,2979oC T (1) ta c: p = . = 1,0638( atm).

+ t = 65,29790 C.+ p = 1,0638 (atm).

Bi 3: Cho mch in xoay chiu nh hnh v (cun dy thun cm). t vo 2 u AB mt in p . Nu mc vo hai u MN mt ampe k nhit (Ra = 0) th ampe k ch 1 A, mch c h s cng sut 0,8. Nu b ampe k ra v mc vo MN mt vn k nhit (Rv = ) th vn k ch 200 V, mch c h s cng sut l 0,6. Tm U, R, L, C.

+ n v tnh ca in p l vn , in tr l m , t cm l Henry v ca in dung l micr fara .Cch giiKt qu

+ V Ra = 0 nn mch ch c R nt C : cos1== 0,8 (1)+Khi thay vn k th mch c R, L, C nt : cos2==0,6 (2)+Vy: (3)

+Mt khc : U = Z1I1 = Z2I2 (4) I2=0,75(A) (5)

Vy : ZL=266,7 () (6)0,8488 (H) (7)

Theo bi : cos21+cos22=1 (8); m cos21+sin21=1 (9)

T (8), (9) cosv (10)

+T gin vect ta c :-Xt OHP c Z1=nn

Ta c : R=Z1cos1 v Z1I2=ZL.I2cos R=ZLcos1cos2 =128 ()

- OPQ cho ta : OP2=PH.PQ hay I22Z12=I2ZC.I2ZLZ= (11)

Vi : Z1== 160 () ZC = 96 ()C = 33,1573 (F)

+U=Z1I1=160.1=160 (V).

+ U = 160V.+ R = 128.+ L = 0,8488H.+ C = 33,1573F.

Bi 4: Mt lng knh c gc chit quang A = 600. Chit sut ca lng knh ph thuc bc sng theo cng thc: ( tnh bng n v ). Mt khe sng E pht ra chm sng song song hp gm hai nh sng n sc v ti lng knh vi cng gc ti i = 600. Sau mt l ca lng knh, t mt thu knh hi t c tiu c f = 20 cm c trc chnh trng vi mt trong hai tia l. B qua s tn sc ca thu knh.

a/ Tnh chit sut ca lng knh ng vi hai nh sng n sc v .

b/ Tnh khong cch hai nh ca khe E cho bi hai nh sng n sc trn mt phng tiu nh ca thu knh.

+ n v tnh khong cch l centimt .

Cch giiKt qu

a/ Tnh ng: .

b/ Tnh ng vi : .

Tnh ng vi : .

Tnh ng gc lch gia hai tia l khi lng knh l: .

Vit c: . Tnh ng: .

a/.b/ .

Bi 5: Chiu bc x c bc sng ( = 0,4(m vo mt tm kim loi ca mt bn t in.

a/ Hiu in th hm trn hai bn t in bng bao nhiu lectron quang in thot ra t kim loi bay trong khng gian gia hai bn t v dng ngay trn bn th hai. Tnh in tch ca t lc . Bit din tch ca mi bn S = 400 cm2, khong cch gia hai bn t l 0,5 cm.b/ Tnh vn tc ban u cc i ca lectron quang in khi catot l km c cng thot v khi catot l kali c gii hn quang in .

+ n v tnh ca hiu in th l vn , ca in tch l Cu-lng v ca vn tc l mt/giy .Cch giiKt qu

a/ Ta c : W0max = A + eUh Uh =

1,075V

+ Hiu in th ny c to bi in tch +Q trn bn c chiu sng. Ta c: Q = CUh vi C = = .

Q = 1,2.10-10C.b/ Tm v0max?

+ Hin tng quang in xy ra khi catot l kali

+ T PT Anhxtanh suy ra : = 6,22.105 m/s.

a/ Uh = 1,075V.+ Q = 1,2.10-10C.

b/ v0max = 6,22.105m/s.

Bi 6: o phng x ca mt tng c bng g c khi lng M l 8 Bq. o phng x ca mu g khi lng 1,5M ca mt cy va mi cht l 15 Bq. Xc nh tui ca bc tng c. Bit chu k bn r ca C14 l 5600 nm.

+ n v tnh ca thi gian l nm.Cch giiKt qu

Ta c : , suy ra H t l vi khi lng m ca vt.

Nh vy mu g khi lng 1,5M ca cy mi cht c phng x 15 Bq th suy ra mu g c khi lng M ca cy mi cht c phng x H0 = 10Bq.

H = 8Bq ; H0 = 10Bq.Vit c: .

Tnh ng: t = 1802,7973 nm.

t = 1802,7973 nm.

---------HT--------Ghi ch: Cn b coi thi khng gii thch g thm.

M

C

L

R

N

B

A

Q

Q

I2Z2 I2ZL+

2 I2R H +

O 1 I2 i2

I2Z1 I2ZC

P

Trang 6/5

_1415457950.unknown

_1415565803.unknown

_1415565811.unknown

_1415589701.unknown

_1415589947.unknown

_1415590035.unknown

_1415590063.unknown

_1415590097.unknown

_1415589996.unknown

_1415589810.unknown

_1415589902.unknown

_1415589791.unknown

_1415568102.unknown

_1415568881.unknown

_1415570741.unknown

_1415568867.unknown

_1415567855.unknown

_1415567906.unknown

_1415565812.unknown

_1415565807.unknown

_1415565809.unknown

_1415565810.unknown

_1415565808.unknown

_1415565806.unknown

_1415565804.unknown

_1415565805.unknown

_1415565735.unknown

_1415565739.unknown

_1415565801.unknown

_1415565802.unknown

_1415565800.unknown

_1415565737.unknown

_1415565738.unknown

_1415565736.unknown

_1415465854.unknown

_1415466071.unknown

_1415512433.unknown

_1415565734.unknown

_1415513486.unknown

_1415465956.unknown

_1415465795.unknown

_1415465567.unknown

_1256308729.unknown

_1256309216.unknown

_1415450340.unknown

_1383900151.unknown

_1256309019.unknown

_1256309064.unknown

_1256309095.unknown

_1256309036.unknown

_1256308827.unknown

_1256308975.unknown

_1256308989.unknown

_1201666710.unknown

_1201667849.unknown

_1201667869.unknown

_1201668222.unknown

_1201668620.unknown

_1201668838.unknown

_1201668569.unknown

_1201667960.unknown

_1201667566.unknown

_1201667482.unknown

_1201667001.unknown

_1201667079.unknown

_1201666426.unknown

_1201666575.unknown

_1201666218.unknown