gini thich hiQntucrng khirc xa.[r]
(1)I so GrAo DUC & EAO TAO QUANG TRI
rxr5onsrrrt\ cxsxtsr,$; er* o0s
on rnr rntl 16r NcnrFr rnrr- NAnn zozo \l\bnt\i'.\ f;T Li
Thdi gian ldm bdi: 50 philt (40 cdu triic nghiQm)
(De thi g6m c6 04 trang)
Ho, t6n thi sinh:
SO b6o danh
Ciu 1: Theo dinh 1u0t khirc xp 6nh s5ng thi
A g6c t6i t[ng bao nhi6u lAn, g6c khric xa ctng t[ng bAy nhi6u lAn
B g6c khirc xp 1u6n l6n hcrn g6c tdi.
C tia khirc xp vd tia t6i lu6n ngugc chi6u
D tia khric xa vd tia t6i nim trong ctng mQt mflt phing ggi ld mat phing t6i.
Ciu 2: Dat diQn 5p xoay chi6u u =Uo cos(at + rp) vdo hai d6u dopn m4ch g6m diQn trd R mEc nOi tl6p
v6i tU diQn c6 diQn dung C T6ng trO cta tlopn mpch ld
A. R2- B R, _C,A} -t-'
C2at2' D. +(Ca)2
Me da thi 137
c lir xtty
(t )'
lc, ) C R2
Ciu 3: Hi6n tugng t6n s8c dugc irng dung
A gini thich hiQntucrng khirc xa B th6ng tin 1i6n l4c bing s6ng v6 tuy,5n
C m6y quang ph6 lnng kinh D tiQt trung thgc ph6m tru6c khi tl6ng g6i
CAu 4: Nguy6n t8c hopt dQng.cira thi6t bi ndo sau ddy khOng dga tr6n hiQn tuqng c6m ring tlien tu ?
A M5y phat diQn xoay chi6u mQt pha B DQng co kh6ng tl6ng bQ ba pha
C M6y bi0n 6p D Bdn ld diQn
Ciu 5: TOc d0 truydn Am c6 gi6 tri nhO nh6t m6i trucrng ndo sau ddy?
A Nh6m B Kh6ng khi d 0"C C SEt D Nu6c bi6n o 15"C
Cffu 6: MQt ch6t ditim dao tlQng tti6u hda v6i phucrng trinh x : Acos(ail + cp), gia t5c cira chdt ditim c6
gi6trl cgc dpi li
A Aaz B -a'x C A2o D Aat.
Cflu 7: Tai hai di€m A, B trdn mflt nu6c c6 hai ngudn s6ng k6t hqp ctng pha PhAn tu nu6c tpi trung
dii5m ctra do4n thlng AB dao dQng
A vdi bi6n d0 cpc dai B v6i bi6n d0 cuc tii5u
C ctng pha v6i hai ngudn D nguoc pha v6i hai ngudn
Ciu 8: MQt ch6t di6m c6 khOi lucr-ng m dao dQng di6u hda v6i tAn sd g6c at vd bi€n dO A.Li dQ vd vpn t6c cria ctr6t Oiem tpi ctng mQt thoi di6m ln x virv DQng ndng cgc dpi cira ctr6t ei6m h
, I 1)
mv'+-mc)'x'.
2
maA
s 1
2
p 1
2
mx'
2
mv
,1
-+-2 mv
r1)
s 1
2
2
CAu 9: C6ne tho6t dti brit Olectron ra kh6i bO m{t mQt kim loai ld A Ggi h ldhilg sO Pling,
t6c d0 6nh s5ng trong ch6n kh6ng Chi6u vio kim lopi ndy bric x4 diQn tu c6 budc s6ng ,2' D6
ra hiQn tuqng quang iliQn thi
A.t>!9 AhcAhc B.),<!- c.).<!9 D.).>!.
Cflu 10: D[t l6n lucvt c5c ngo4i lgc cu0ng bric bi6n thi6n didu hda theo thoi gian v6i ctng bi6n dQ, c6
tin s6 lAn luqt ld7 : 20 Hz, fz: 14 Hz, fz : 8 Hz, fi : ) H, vdo mQt l6c cO.tan si5 dao t1Qng ri6ng ln
I4Hz Con lic dao dQng cu6ng birc v6i bi6n <10 l6n nh6t img vdi ngo4i luc co tdn s6
Lfr B.fi C.fi D.f4.
(2)Ciu 11: Hat nhdn lx cO khOi luqng m Ggikh6i luqng cira pr6t6n vd notron 6n luqt ld mpvd mo, d0 6nh s6ng chAn kh6ng ld c Ndng luqng 1i6n ktit ri6ng cria h4t nhdn ndy ld
A. lZ*r+(A-Z)m^-*7r' B lz*o+Am,-m)c'
A
C lZm, + (A- Z)m, - m)
A
o lzmo + Amo - *1"'
Ciu12: MQt s6ng co hinh sin c6 chu ki ld f, tAn sO ta; t5c d0 truydn s6ng li v thi budc s6ng ld
A ).=: B l.:T.f C.2:+ D ).=v.f rf
Ciu 13: DiQn 5p xoay chidu u:(Jocos(100at + nl6) (/ tinh bing s) c6 tAn sO g6c bing
A.50 radls B 116 radls C.Zr radls D 100zrad/s
Ciul4z Trong chAn kh6ng, s6ng diQn tu c6 tAn s5 ndo sau ddy ld s6ng v6 tuy6n cgc ng6n?
A 8 MHz B 5 MHz C 0,3 MHz D 900 MHz.
Cflu 15: Mach dao dQng li tuong gdm tu diQn co diQn dung C vi cuQn cim thuAn c6 h0 s,5 t.u ca- Z Chu ki dao dQng ri6ng ctra m4ch ld
tlrr
A T:)- lL '"\lc B " -L'LY, T:z*,[tc C T: -:- D T = ]-JLC
2;@' u" 2r
Cffu 16: MQt ch6t ph6ng xp c6 chu ki bin rd ld 7 Ban dAu co 1/o hat nhdn ch6t phong xp ndry, sau kho6ng thdi gian nio sau ddy thi sO trat nhAn chAt ph6ng xg ndy cdn lai lit Nol2 ?
A, N=27 B N:7 C Lt=L D Lt:L.
42
CiulTzV6cto culng d0 diQn truong gdy rabdi mQt diQn tich di[m Qc6 chi0u
A huong rlxa Q n6u Q < 0 B 1u6n hudng vO phia Q.
C hucrng vO phia Q ndu Q < 0 D lu6n hufng raxa Q.
Ciu 1"8: Khi dQng co kh6ng d6ng b0 ba pha hopt dQng 6n dinh thi t6c cIQ quay cira r6to
A bdng t6c d0 quay cira tri trulng B lon hcrn t6c <IQ quay ctra tu truong
ft
C gAp r/3 ldn t6c d0 quay cira tri trucrng D nho hcyn t6c dQ quay cria tu trucrng
CAu 19: X6t nguyCn tu hitlrd theo m6u nguyCn tu Bo voi ro ld b6n kinh Bo Tr4ng th6i drmg cria nguy6n
tt img vdi b5n kinh qu! dpo drmg cira 6lectron nio sau d6y ld tr4ng th6i ccy bin?
A 16ro B ,o C 4ro D 3610
Ciu 20: Tia ndo sau ddy kh6ng c6 b6n ch6t s6ng diqn tu?
A.Tia a B Tia hdng ngo4i C Tia tu ngo4i D Tia X.
Ciu 212 Trong thi nghiQm giao thoa khe Y-ing v6i 6nh s6ng dcrn sic c6 bu6c s6ng 0,5 pm, ti s6 gita
khoing c6ch tu hai khe d6n mdn vd khoing c6ch gita hai khe ld 1,5.103 Khoing vin quan s6t duoc tr6n mdn b[ng
A 0,5 mm 8.0,75 mm C 0,75 m D 0,3 mm
Cil22: M6t con l6c dcrn c6 chiAu dei 80 cm, dao dQng v6i bi6n d0 g6c ld 5o Bi6n dQ dao dQng cira
l[c ld
A 0,7 m B cm C.4 m D.4 cm
Cflu 23: Dit mQt hiQu diQn thti khdng dOiZ+ V vio hai dAu mQt do4n mach thi cudng dQ dong diQn chay qua dopn mpch ld2JrA C6ng su6t ti6u thu diQn ndng cria dopn m4ch ndy ld
A 96 W B 48 W C.24o W D 48 o W
Chu 242 Cho ph6n img h4t nh?'n lHe +'lw * lX + itt 56 nortron ctra hpt nhdnXld
A 17 8.25 C 9 D 8
C6u 25: Dat mQt diQn 6p xoay chi6u u = 220Jicos(1002r + d U) vio hai d6u dopn mpch RLC nf,i ti€p
thi culng d0 ddng diQn qua doan mpch li i = Ocos(100 nt) (A) Bitit c6ng su6t tiCu thu dign ndng cira do4n mpch ln 39 W Gi6 tri cta gbitg
(3)I C6u 26: TrCn mQt sgi ddy ddn h6i hai diu cO Oinn ddi2,4 m dang c6 s6ng dimg v6i bu6c song 60 cm
56 bpng s6ng trdn ddy ld
4 t2 8.4 c 8 D 6.
ciu27: MQt th6u kinh hOi tr,r c6 ti6u cp ld 25 cm, d6 tu cua th6u kinh ndy bing
A.0,05 dp B 5 dp C.4 dp D 0,04 dp
CAu 28: Hai lic ld xo A vd B nhu rlirr, ctng dao dQng di6u hda v6i bien dQ l5n luqt lit Ar :10 cm
vd Az: 4 cm Ti s6 tlQng ndng cira l6c A vntQng narg .o, lic B khi chirng ctng di qua vi tri cdn
rJ Dang ta
4.2,50 B 0,04 c 0,16 D.6,25.
Cdu 29: ei6t hing so Pl5ng Id h:_6,625.10-3aJs Anh s6ng d<rn sic c6 tdn s5 5.10ra Hz ducrc tao thdnh
btti cilc ph6t6n mang nlng luqng bing
A 1,1041.10-27 J- B 3,3125.10-te J c.3,3125.10-20 J D 1,1041.10-2s l.
C6u 30: D[t mQt diQn.ap xoay chi6u co gi|tri hiQu dsng Uvdo hai dAu doan mach gdm tu diQn m6c n5i
ti6p v6i cu6n.c6m thuAn Khi d6 di6n 5p hiQu dsng hai dAu tr; tliQn lA 30 V, t1iQn ep hiQu dUng hai ttAu
cuQn c6m thuAn le 40 V Gi6 tri cria Ubing '
a - -
-' A 10 V B 50 V c 70 v D 50.,8 V.
Ciu 31: Trong chdn kh6ng, b1rc xp dign tu c6 bu6c s6ng 2r : 10 pm thuQc vung h6ng ngoai, birc xa
diQn ttr c6 bu6c s6ng Az: l0-e m thuQc vtng tia x Ti sigita tAn s6 tia hdng ngJpi
"alirisO iiu x Ai
cho o trOn bing
A 10-3 B 104 C 103 D 10-4.
Ciu 32: M$t s6ng dign tu c6 chu ki 0,25 prs, truydn m6t m6i trucrng v6i bu6c s6ng 60 m T6c d0 s6ng diQn tu m6i trudng ndy ld
A.2,40.108 m/s 8.2,25.108 m/s c.3,00.10s m/s D.0,15.108 m/s.
C0u 33: Hai dao dQng ili6u hda ctng phuong c6 phucrng
trinh ld xt = Acos(at + rpr) vd xz : 4cos(rtt + g) D6 thi bi6u di6n sg bitin thi0n cria xr vd xz theo thdi gian r nhu
hinh v6 T4i thcri di6m r :0 thi pha cria dao dQn! t6ng hqrp
cria hai dao dQng tr6n bing
B xl6 D.5r/6 J .6, -.6 -3 x(cm) {(cm) r(s)
A 0
C rl3
CAu 34: MQt con ldc.lo xo dang dao cl6ng di6u hda theo phucrng thing drmg (dAu tr€n lo
^o .5 dinhldAu du6i lo xo gin v6i v4t n[ng) OO thi bi6u di6n ss bi6n thi6n cria chi6u ddi
( ctla ld xo theo thdi gian r dugc cho nhu hinh vE Ldy g: t m/s2" giiSt dQ ctmg cira tO xo ld 120 N/m, luc tlnn h6i .,iJtO
"o
c6 dQ lcrn cuc dai bing
A 12 N B 22,9 N.
c 10,9 N D.24,2N.
lt
I
l. t
- r r .1-I t I t, -r 40 20
t
-I I
-a { -F-tll -{ -t -rrtl
- - l- ltlltl| i-r - l- - -!- I .1 -r-
l-ltlltltr
lttltlt r(s)
9
Ciu 35: Q*u} s6t s6ng.drmg tr6n sqi ddy AB, dAu A dao itQng tli6u hda theo phucrng vu6ng g6c v6i sgi
9:f Xt tgn s,O4t1aV AOi Auqc, A dusc *.* ia nirt Khi diu B Lu vdl: 22 Hzthi tr6n diy c6 nrit
N6u d6u B c6 dinh vd coi t6c tto truy6n s6ng kh6ng aoi, ac tr6n d6y c6 nrit thi gi6 *i c1pfkji d6 ln
A 15 Hz B 16 Hz C.20 Hz D.24 Hz.
Ciu 36: Ept diQn 6p xoay chi6u u = u Ji cos(l\\rt + @ (U ldrfing doi) vdo hai dAu dopn m4ch RrC ri;i
ti6p c6 C thay doi duqc Ei6u chinh C dc he s6 c6ng suAt cria riach ld 0,8 thi c6ng su6t iicu ,t o .t u mach le 100 W Khi di0u chinh C dC mach *iy ,ucQrig huong tliQn thi c6ng *i, ril,i1"f,o trl, iu.f, 1.1,i
d6 le
A 186,45 W B 140,56 W c.201,15 W D 156,25 W.
Ciu 37: Tai hai didm A, B tr€n m[t ch6t l6ng c6 hai ngu6n s6ng k6t hqp ctng pha dao dQng theo
phucrnglhing dung Tpi ditim M tr€nm[t ch6t lSng c6 cyc?pi gir" ti"" Fii6i ea :25
cm, AM:15 cm,
MB
: ?0 cm, gita Y "d 1"Tg trung tryc c:ira AB c6 2 vdn giao thoa cuc ti6u Tr6n dudn g thing ua, ,6
cpc ti6u giao thoa nlm gifta Mvd B lir
A ln r) r^
)
{
(4)Ciu 38: MQt lEc ld xo dflt tr6n m{t sdn nim ngang khdng ma s6t nhu hinh v6 Lo xo nhg c6 d0
[: 100 N/m, vft nho c6 ktr6i luqng m: I kg, mang Q: l}'s c chqn tryc oxgan vor mat ,! , san, song song v6i tryc ld xo, chiOu ducrng hudng xa dinh k m
E
cua lo xo Khi ld xo kh6ng bitin d4ng
diQn tich
-.,1
dlem co
kh6ng gian img v6i x > 0 c6 mQt diQn
thi v4t g6c tqa dQ O
trulng d6u mi v6cto
MiAn cudng
+
x
dQ diQn trucrng cung hu6ng truc Ox vd c6 d0 l6n E: 5.10s V/m.
Ban dAu ngudi ta git m b vi tri ld xo n6n 10 cm rdi th6 nhg tpi
dugc tinh tri /:0 di5n thoi di6m vflt d6i chi6u chuy6n dQng lAn thtr
thoi di6m /:0 Qu6ng ducrng vat di
2020bins
A.612,45 m B 528,84 m C 167,78 m D.200,28 m
Ciu 39: Dat mQt ttiQn 6p xoay chidu u:(JJicos(100ar+p) (V) vdo hai ddu cuQn dopn m4ch AB mdc
n5l t6p theo thf ry g6+ diQn tro R, tu diQn c6 diQn dung C, cu6n cim thuAn .9 hC
:6 F:{T Z thay d6i dugc Gqi M li di6m nim gita tU dipn vdL cuQn cdm Khi L: Lt vd L: Lzthi diQn 5p hai ddu cuQn cim
bing nhau, d6ng thoi cudng tlQ ddng diQn qua mpch hai trulng hqrp lQch pha mQt g6c xl3
DiQn 6p hiQu dtmg tr6n dopn AMkhi L: Lt vd L: Lz ch0nh lQch mQt luqng bdng
A uJT B u c o,su D uJ,
Ciu 40: DiQn nlng tu nhd mby phdttliQn xoay chi6u dugc truydn di5n noi tiOu thu bing duolg ddy mQt pha Ban AAu Aq glPji?"r6p trdn ducrng day bing l0% diQn 6p cirtr-tii ti6uthu Xem hQ s6 c6ng suAt cua mAcn rnryen tar 1u6n Uing f Can phai teng diQn 6p dAu ilucrng d6y truy6n tdi l6n bao nhi6u lAn de gi6m c6ng su6t hao phi tr6n ducrng truydn 100 16n nhrmg v6n dim bdo c6ng suAt noi ti6u thg nh{n dugc ld kh6ng d6i?