<span class='text_page_counter'>(1)</span><div class='page_container' data-page=1>
0I phaong dn trd loi hqp
g
nhdt
Ciu
1: Mach dao <sub>ddng c6 C = 6nF, </sub>
<sub>L </sub>
<sub>= </sub>
6
p
H. Do m4ch c6 R <sub>= </sub>0,5 C), nen dao d6ng trong mach trit ddn. Dd
duy
tri
dao dOng vdi hiQu diOn <sub>thd cuc dai gifra hai </sub>
<sub>bin </sub>
ru diOn
li
Uo
<sub>= </sub>
10V
thi
phaild
sung nang luong cho
mach m6t cdng sudt
li
A.
P:
15 mW
B.P=20mW.
C.
P:25
mW
D. 30 mW
A.L:2mm
B.
L:3
mm <sub>C. </sub>
L:4
<sub>mm</sub> <sub>D. </sub>
<sub>L:5 </sub>
<sub>mrn</sub>
Cfra?z Song diQn
tt
c6 budc s6ng 12 MHz rhu6c loai s6ng nbo du6i ddy ?
A. s6ng cuc
ngln
B. s6ng
ngin
c.
s6ng
tru.rg
- D. s6ng ddi
Cf;u
3:
Phdt bidu nbo sau ddy sai khi n6i vd s6ng diQn
rt
?
A.
Song diQn tir mang ndng
lucrng
B. S6ng di0n tX l*r6ng truydn duo. c trong ch6n kh6ng
c.
s6ng diQn
tt
li
s6ng
ngang
<sub>D. s6ng </sub>diQn
tt
truydrl dugc trong chan khong
Cfiu
4:
Trong
thf
nghiQm <sub>giao thoa 6nh s6ng </sub>
<sub>v6i </sub>
<sub>khe </sub>Young, chi6u d6ng
thoi
hai bric ua Ao'n s6c c6 bu6c
96ng l'1 = 0,48pm
vi
)u2 = 0,64pm.
Nguli
ta th6y vdn s6ng
bfc
4 cria
bfc
ia
i,.1 trung
vdi
v6n s6ng bSc k cria
l.z . Giri tri cria k
li:
A.2
B"
3
c.4
<sub>D" </sub><sub>5</sub>
Ciu
5:
Quang ph6 li€n tgc
A, phu thuQc
vio
nhiet dO cria ngudn phdt
mi
<sub>th6ne </sub>phq thuQc vdo bAn chdt
cta
ngu6n ph6t.
B. php thugc
vio
bAn chAt
vi
nhigt dQ cta nguAn ph6t.
C. kh6ng phg thuQc
vio bin
ehdt
vi
nhigt d0 cria ngu6n phrit.
D. phy
tlu0c
vno
bin
chdt cria ngudn phrit me kh6ng ptrlr ttruQc
vio
nhigt dQ cria ngu6n ph6t.
Cffu
6:
Trong
thi
nghiQm
Young
vO giao thoa 6nh s6ng, khe hpp S ph6t
ra
ddng
thoi
ba b{rc xa don s$c
c6
busc
s6ng
li
?v1: 0,421tm,
1"2:0,56pm
vi
1.3
:
0,63pm. Tr6n
min,
<sub>trong </sub>
<sub>khoang </sub>
<sub>dta </sub>
<sub>hai v6n </sub><sub>sdng</sub>
t.^ ,.K ,t
li6n ti6p c6
miu
gi6ng
miu
vAn trung tAm
thi
s6 vAn sdng quan s6t duoc (hai v6n
rei{t*ng
nhau
dug-dnh le mQt vdn) ld
h.20.
B.
21.
..
c.
26.
D. 27 .
Ciu
7: Tia Ronghen cd
A.
cing bin
ch6t
v6i
s6ng v6
tuydn.
B. cirng
bin
ch6t
v6i
s6ng 6na.
C. diQn tich
6m.
<sub>D. </sub>
<sub>bu6i </sub>
<sub>s6ng </sub>
<sub>l& </sub>
<sub>hon buEc </sub><sub>sr5ng </sub><sub>tia h6ng ngoai.</sub>
CAu
8:
Trong ch6n kh6ng, cScbuc x4 dugc sap x6p theo thri tr,r bu6c sdng gi6m dAn
h-A. 6nh s6ng tirn, tia hOng ngo4i, tia tu ngo3i, tia Ron-ghen.
B. tia Ron-ghen, tia tri ngop!, rinh s6ng tim, tia h6ng ngopi.
C. tia hdng ngo4i, rinh sSng tim, tia tir ngopi, tia Ron-ghen.
D. tia h6ng ngoai, 6nh s6ng tim, tia Rcrn-ghen, tia tfr ngoai.
Ciu
9: Trong
thi
nghiQm Young <sub>vd giao thoa 6nh s6ng, khoAng c6ch gifra </sub>
<sub>hai </sub>
<sub>khe a </sub>
<sub>= lmm, </sub>
<sub>tt </sub>
<sub>2 </sub><sub>khe ddn</sub>
mhn D" <sub>=2m. </sub>Ngudn S c6ch hai khe
lm
ph6t ra brlc xa
c6
.L <sub>= 0,6 </sub>
pm,
Di chuydn S m6t doan
L
theo phucrng
SrE dd vAn sdng trung mm di chuydn ddn trDng vdi vAn sr{ng
thrl5.
Gi6
tri
cria
L
ld
-
----
<sub>- </sub>
E
TRUCNG
DAr riQC
KX{OA
<sub>Erqc TUNHrEN</sub>
rR
uo
N c_
r:%.:-:YEr{
<sub>K rr </sub>
rN
Mdi cdu cd 04 phuong dn
tni tdi,Thi
sinh chon m6t
pii
<sub>rHr rr{r}DAr Hoc </sub>
<sub>LAN </sub>
<sub>rr </sub>
<sub>NAM </sub>
<sub>HCIc 201r </sub><sub>- </sub><sub>z&rz</sub>
MON
THr:
vAr
lf
Thoi gian ldm
bdi:
90 phrtt
Ma
d6:777
CAu
10:Jlolg
giao thoa 6nh sring cria lu6ng ldng kfnh, c6c l6ng
kfnh
g6c
chitit
quang ld 4.10-3 rad, chitit
suAt n
=
1,5.Ngudn dcrn s6c.c6
l.=
0,6pm cdch lud'ng l6ng kinh
<sub>-Ot </sub>
Coai
<sub>d:50 </sub>
cm, mdn c6ch lu&ng ldng
kinh
L:
1,5 m.
Khoing
v6n
i
c6 gi6
tr!
li
A.
i:0,2
mm
B. i = 0,3
mm
<sub>C. </sub>i
-
0,4
mm
D.
i = 0,6 mm
Cf;u 11: <sub>Quqng </sub>ph6 cria
m{t trdi
quan s6t du<rc trdn
m{t
d6t
h:
A. <sub>Quang </sub>ph6
vph
phdd
xa
<sub>B. euang ph6 li€n tuc</sub>
9.^QT:gihd
vpch h6p
ths
D.
quan!
pfrO tien tuc xen k€
vdi
quang ph6 v4ch
Cf,u 12: Trong thf nghiQm Young vA giao thoa 5nh sdng,
khoing
c6ch
gita
hai khe a
:
1 mm, tu hai khe Otin
ldn
D
:
2
rrt, ngudn s6ng gdm 2 bftc xa don sfc c6 1,1 = 0,5 pm
vi
7v2
:
A,6 pm. Khoin
g
ca"Lnho
,hatgifru
hai vdn silng
ctng miu
tr€n mdn ld:
A.
1,2 mm
B.3mm
</div>
<span class='text_page_counter'>(2)</span><div class='page_container' data-page=2>
Trw{t-ns THPT chuv€n KHTN"
di
thi tht? Dai ttoc IAn
II
ndm hoc
20tI
-
2012
.
.
Trcne4L
Cfu
13: Con
llc
id
xo
dao dQng di€u hda theo phuong
thing
dtmg
vdi
chu
ki
T
:
0,4 s, bi€n dd
A
:
8 cm.
Cho g
:
l0
m/s2 vd n2
:
10.
Thdi
gian
ngin
ntr6t a6
vit
di
tir
vi trf
cdn
bing
d6n
vi trf
ld
xo
c6 chiAu ddi
tu
nhi6n
li.
A.
1/10 s.
B.
1/15 s. C.
l/20
s.
C0u
14: Ccn l6c
lb
xo
dao d6ng didu
hoi
vdi
biOn Cd
A
<sub>= </sub>
2
cm, chu
ki
T
=
1,?s, pha ban ddLr
ld
2n /3"
Qu6ng duong
con
l5c
di
duoc trong 4s ddu tiOn lb
4.25
cm
8.26
cm
C.27
cm
D.28
cm
Cfiu
15: Trong mQt dao dQng diAu
hoi, khi
vdn
tdc
cria
vit
bing
mQt nria v$n ti5c cgc d4i cria n6
thi
ti
s6
gifra th6 n6ng vd d6ng nEng
li:
<sub>'</sub>
A.2
8.3
c.
t/2
D.
l/3
CAu L6: Con i6c lb xo c6 kh6i luong m
<sub>= </sub>
100 g, dao dQng didu
hoi
vd
cd n5ng E
=
32mJ. T4i thdi didm ban
ddu vAt c6 vfln tOc v
<sub>= </sub>
40.6
cm/s vd gia toc u <sub>= </sub>8
*/rt.
Pha ban ddu cria dao d6ng
li
A.-lt/6
B. tr /6 C.
-2n
/3
D.-n/3
Ciu
17: M$J
v{t
dang dao dQng co hgc,
khi
xhy rahipn tugng cdng hudrng,
vft
se ti6p tr;c dao dQng:
A.
Vdi
tAn sti nhd hcn
tin
s6
riOng
B. Ift6n.g con chlu t6c dr,rng cria ngopi lgc
C.
Vdi
t6n sd
bing
t6n sti
ri6ng
D.
V6i
tdn st5 lorn hsn t6n sli ri€ng
CAu
18:
Con
lic
ld xo dao dQng diAu hda theo phucrng
thing
drmg
v6i
tAn s6
f
:2,5
F{2, trong
qui
trinh dao
dQng thi
tf
sii
gita
lgc
din
hdi cpc d4i
vi
cpc ti6u H 3. Cho n2
:
10. Gia t6c cgc dpi cria dao dQng
h:
A.
3
m/s2.
8.4
rn1s2.
C.5
rdsz"
D.6
n/s2.
Ciu
19: Chon c6u sai trong c6c cAu sau khi n6i vd n6ng iugng trong dao d6.ng didu
hol
A.
Khi
d6ng ndng tiing
thi
thd n[ng
giim
B.
Khi
v{t
& vi trf cdn
bing thi
d6ng ndng cira vAt lon nhdt
C. Khi vQt 6
vi
trf biOn thi thd n[ng 16n
nhdt
D.
Khi
vAt chuydn d6ng theo chidu duong
thi
thd nd.ng tdng
Cffu 2S: MQt oon
lic
ld
xo
c6
kt6i
luqng
vft
nh6 ln 50 g. Con
lic
dao dQng diAu hda theo mQt tryc c6 dinh
nem ngang
v6i
phucrng
trinh
x
= AcoscDt. Cri sau nhfing
khoing
thdi
gian 0,05 s
thi
dQng nEng
vi
th6 ndng
eria
vft
lai
bing
nhau. L6y n2
<sub>=lA. </sub>
Lb xo cria con l&c c6 d$ e{rng
b[ng
A. 50 N/m.
B.
100 N/m. C.25 N/m.
D.200I.[/m.
Cdu
21:
Con l6c ld xo c6 m
:
1 kg, dao dQng diAu
hoi
vi
c6 co nSng E
=
125 rnJ. Tpi thdi di6m ban ddu v6t
c6 vAn tdc v =
25
amisva gia tOc a = -
6,25.5
nVrt. Th6
n[ng
con !8e
t4ithdl
di6m t
:4,25T
iit
A.3i,25
m.n B.62,5 mJ
{,&ur22z MQt
v{t
tham
gia
ddng
thdi hai
dao dOng didu
xz=
2cos(IAnt
<sub>-n /2) </sub>
cm . VQn tdc cria vat khi
t
<sub>= </sub>
8s lh
A. 20 cm/s
B.
40J2
cmls
C..20r
cmls
D.40r
cmls
D.
l/30
s.
C6u
23:
MQt con l8c ld xo dao d6ng-di€u hda theo phuong.ngang
v6i
tAn sii g5c 10 radls.
Bitit ring khi
ddng
n6ng
vi
thrS n[ng
bing
nhau
thi
v6n t6o er]a vdt e6 dO l6n
bing
0,5 rnls. Bi€n
*6
C"o dgng ofia con
lio
li
B.
5J2
cm
D.
10JI
cm
C.93,75
mJ
D.
25 mJ
hba
c6
phuotrg
trinh
: \=
Zcosl}nt
cm
vh.
A.5cm
C.5
cm
::$,3i;fl'."ft'J'ffi*
flftilT#lH:'uut
'uil.
si€u 6m c6 thc truydn dusc trong ch6n kh6ng.
C. Si0u 6m c6 t,An s6 l6n hon
2AkHz.
D. Si€u 6m c6 thO truy€n dugc trong chdt
rin.
C6u
25:
T4i mQt di6m crieh ngudn Am 10 m
thi
s6 mfrc
culng
d0 6m ln 70 dB. H6i t+i mQt di€m c6ch ngudn
0m 1m thi c6 mric
culng
d0 Am
li
bao nhi6u ?
A.
50 dB B. 60 dB
c.
80 dts D. 90 dB
Cdu
26:
Tr6n mQt sgi ddy dnn hdi dei 1,2 m hai
diu
c6 dlnh dang c6 s6ng dirng, ngodi hai dAu dAy cO dinh
cdn
c6
hai di6m khdc tr6n ddy kh6ng dao
dQng vA
thdi
gian
gira
nai l6n ti6n
iiep
sgi d6y dudi
thing
ln
0,05 s. VQn tde truyAn s6ng.tr0n dAy ln :
A. 5 m/s.
B.
i2
m/s.
C.4
m/s. D. 8 m/s.
C;dw27t M$t s6ng co lan truyAn trong mQt mdi truong
v6i
tdc dQ l20cm/s, tAn sd cria s5ng thay d6i
tir
l0FIz
d(in 15H2. Hai diiSm cSch nhau l2,5cm lu6n dao dQng ru6ng pha. Budc s6ng cira s6ng co AO
ta:-A.6,25
cm
B.
12,5
cm
C. 5
cm
D.
l0
cm
Cf;u 2E: Khi c6 s6ng
dtng
tr6n mOt soi day dbn hdi AB hai ddu cd dinh thi th6y rren ddy c6
7
nfit. Bidr tdn so
s6ng lh 42H2"
Vdi
day AB vh vAn tdc <sub>truydn s6ng nhu tr0n, mudn trdn ddy c6 5 nrit </sub>
<sub>thi </sub>
tAn sd sSng
phii
lb
A,28HZ
B.30Hz
C.63Hz
<sub>- </sub>
..+;.-lli--
.
D.
58Hz
g{'7ir,;;,"";,-}))og
Stu':'*i+-!"&
</div>
<span class='text_page_counter'>(3)</span><div class='page_container' data-page=3>
Trrdnt
\HFT chuv\rt KHTN, di thi thth Dai hoc
lin II
ndm hoc
20It
-
2012
-
Trafte3l4
Cfrw29z Ntiu 6nh sSng di tir m6i trud'ng trong su6t'ndLy sang m6i trudng trong su6t khdc
thi
sd c6 sg thay ddi
c'la:
A.
Vpn t6c vd
tin
sd
C. Bu6c s6ng
vi
v6n trSc
B.HQ sd c6ng'sudt cria doan mach giAm
D.HiOu di6n thdhi€u dung trCn cuOn
cim
giAm
C6u
30:
'frong doan m4ch RLC rt6i tidp dang
x|y
ra cdng huirng. Tdng ,Cdn tdn sd cbng dien
vI
gifi
ngu5rgn
cilc th6ng sd kl'r6c cita m4ch, kdt luAn nho sau dAy dring
A.Cudng d0 hiqu dung cfia dbng didn tdng
C.HiQu diQn thdhigu dung tr0n tg diOn tdng
Cf;u
35:
Dat diQn 6p u
:
Ucos a;
t
vdo hai dAu doan
3LCa2
: i
vi
r =
ZJicoL.
Chgn t<6t tupn dirng:
A. u nhanh pha
r
13 so
v6i
i.
C.
i
nlranh pha n /6 so
vdi
u.
CSu
36:
Mach xoay chidu ndi tidp gdrn curdn dAy c6
I-
<sub>=</sub>
B. Kir6ng c6 gi thay d6i
D. TAn s6 vd budc s6ng
B. u nhanh pha n 16 so
vdi
i.
D.
i
nhanh pha n
/3
so vdi u.
1
i
<sub>FI, </sub>
<sub>r </sub>
<sub>= </sub>
<sub>50 </sub>
<sub>f) </sub>
<sub>vd </sub><sub>tr-r </sub><sub>di€n </sub><sub>C. </sub>
<sub>Khi </sub>
<sub>hi6u </sub><sub>di€n thd hai</sub>
E
CAu
31:
M4ch RLC
n6i
ti6p g,5m
R
biiln OOi,.cugn dAy
thuin cim
c6
L
= ?H,
tu
dien c6
C
:
191p.
p51
7t 7f
vdo hai dAu do4n mQt hiQu diQn th6 (100V - 50FIz).
Khi
mach c6 cdng su6t 40 W thi R c6 gi6
tr!
ld
A.
50 O hopc 200
O
B.
50 Q hoaq 100
A
C.100
O ho[c
200
Q
D.
75fl
hopc 150 Q
CAu32:
Trong doan.m4ch cliQn xoay chi6u gdm diQn tro thuAn, cu6n
cim
thuAn vd tu diQn
<sub>-ac </sub>
n6i titlp thi
A.
di€n 6p giftahai dAu tp diQn ngugc pha
v6i
diQn 6p gi&a hai dAu dopn m4ch.
B. dien 6p giirahai dAu cuQn cAm cing'pha
vdi
diQn 6p gifta hai-dAu
tp
di6n.
C. diQn 5p gitra hai
diu
tp diQn tr6 plra so
v6i
diQn 6p gitrahai
diu
dopn m4ch.
D. diQn
ip
gifrt"hai dAu cuQn c6m tr6'pha so
vdi
diQn 6p
gifa
hai cIAu do4n'mpch
Ciu
33:
Cho m4ch di6n xoay chiAu RLC nOi titip c6 tAn s6
f
thay
d6i
duqc.
Khi
f
:
f1:25
Hzhay
f
: fz:
i00 tlzthi
odng suAi c&a rnacli ldr rrtru rrhau.
H,ii v6i
gi6
tri
ndo ciih
tin
s6
thi
cdng s,rdt cria mach ci,ie d4i ?
A.'75 Hz B. zs
Ji
uz
c.
!o
ru
D. so
Jt
Hz
CAu
34:
DAt hieu diQn
thti
u
=
Uosin2nft
(V) r,ib
hai dAu mach
n5i ti6p
g6m diQn tro
R
:
i00 O,
cuQn
ddy thuAn cdm c6 L
=
iH
vd tu di€n
c
:
10-q
F. ci6 tri
c0a tAn sd
f
de higu di€n th6 tr€n ru dat cqc dai ld
71nTi
A.25
Hz
B.zs
Jt
Hz C. 50
Hz
<sub>D. </sub>
s}J,
Hz
mach gdm cudn ddy
(L, r)
"Oi tiOp tir diQn C thda mdn
ddu doan mach
lb u
=
!20JicosL}}nt
(V) thi
ddng diOn trong mach
id
i
<sub>= </sub>
2,4cos
<sub>Q}az-t </sub>
+
1rl4)
(A).
Dung khrirng cria tu diOn c6 gir{
tri
id
A.
50
f)
B.
100 CI
c.
150
f}
D. 200
o
c.
300 f2
D.450
f'
F
{du37:
MachLCly tu&nggdmcu6ndayLvhtudiOn
C=O,AZ ptr.
Khidaoddngtrongmachdndinh,hieu
,ii€n thd cuc dai
gifa
hai b6n tu diQn
li
Uo =^
I
V
vh cudrng dO ddng di€n cuc dai trong mach lh Io <sub>= </sub>200 mA.
Hidu didn thd gifra hai
bin
tu di€n tai thbi didm cudng dQ dbng di€n trong mach
c6
gi6 rnbang 10b
mA
lb
A.0,3
V
8.0,5 V
C.
0,3..6V
D.0,5""6''l
CAu
38:
Khung chgn s6ng g6m cu6n
citmL
vd 2 tu Ct,Cz. N6u ehi dilng
L
vd
C1
thi
thu duoc s6ng c6 2"1
:
100 rn. Ntlu chi dirng
L
vi
Cz
thi
thu duoc s6ng
Xz:
7 5 m.
Khi
dirng
L vd
hai <sub>tU </sub><sub>Cr </sub><sub>, </sub><sub>C2 </sub><sub>song song nhau </sub><sub>thi</sub>
khung thu duoc s6ng c6 bu6c ld
A.25
m C.125 m
C.
150 m
D.
175 m
CSu
39:
Trong so dO cira m6t mriy ph6t s6ng vd tuy6n di€n, kh6ng c6 mach (tAng)
A. khuiich
d4i
B, ph6t dao d6ng cao
tAn
C. bi6n
di€u
D. rrich s6ng
CAu
40:
Mach xoay chiOu ndi ti6p gdm cuQn ddy thuAn
cim
L,
di6n
trd
R
:
150
Jt f)
vd tu diQn C. D6t vdo
haidAu doan mach hipu diQruth€
u=L|ocosznft(V)
voi f
thay d6i duoc.
Khi
f
:
fr:25Hzhay
f
:fz:
l00Hz
tlri cudng d6 ddng di€n trong mach c6 giStri hi€u dung nhu nhau nltrmg l€ch pha nhau 2n
l3
. Cimldtdngoha
euQn ddy g't;
;:
f1 ld:
A.50 ()
B.
150
f)
@
</div>
<span class='text_page_counter'>(4)</span><div class='page_container' data-page=4>
4
cdu
41: <sub>Trong dong co kh6ng ddng b6 </sub><sub>ba </sub><sub>pha, chgn nhan dinh dring</sub>
4.
Khi
hoar ddng r.hi 16ro IuOn quay ddu.
B. R6to cfia dong
"g.h.ong
odn!
u-o quay vdi tdc dQ g6c cfia tir tnrirng quay.
C. BQ phQn rao ra <sub>tir trubng quay ld </sub><sub>stito.</sub>
Q,
Tt
trudrng rrong dQng co ru6n rhal/ ddi
<sub>ci </sub>
<sub>vd </sub><sub>hu6n-rg </sub>vh
rri
sd.
cfru
42: Mach
utul *?:t.
<sub>chicu noi-riiip gom </sub>
<sub>,u6n </sub>
<sub>a"ay </sub>
9,
.),
mic.nt5i tii5p v'di tu di6n
c.
Bi€t
hiQu diQn th6
gifra hai dAu cu6n ddy lQch pha
<sub>n/ 2 </sub>
<sub>r" </sub>
<sub>u3i rrier </sub>
<sub>eier </sub>
<sub>,it6 </sub>
<sub>git"'rt"r </sub>
<sub>eair </sub>
<sub>o"+ri-u"n. </sub>
<sub>chgn </sub><sub>ph-ucmg </sub>
6n dring:
A.
f
=z{zc-r'):,
",^..-I..,f
=?"ri-i;:'
:C.?:zc(zc-zr).:
<sub>' </sub>
.^''p:i:'irZr_ra.
C6u 43: Mach xoay chidu noi tiiip <sub>gom doari mach </sub>
<sub>AM </sub>
<sub>1g6m </sub><sub>cud" </sub><sub>d </sub>
<sub>ayt,19mfc </sub>
<sub>n6i ti€p </sub>
<sub>v6i </sub>
<sub>aoan </sub>
<sub>Ma </sub>
t"e6-a. ..t <sub>^'r -.. </sub> .
K nOr trep
c)- Kni
uav vu6ng pha
v6i
uys thi he thftc ndo sau d6y ld dring
A.
L
: C.r.R
<sub>B. </sub>
<sub>R: </sub>
<sub>L.C.r </sub>
<sub>C. </sub>
<sub>r:L.C.R </sub>
D. C
:
L.r.R
!6u
la'-vlach
xoay chidu noi tidp_ c6 tdn sd
f
<sub>= 50 </sub>H.z <sub>sdm cu6n day rhudn €6m </sub><sub>L, </sub><sub>diQn </sub>
<sub>tr& </sub>
<sub>R </sub><sub>= </sub>
<sub>i00 </sub>
o
<sub>vi </sub>
<sub>tu</sub>
dien
c.
Thay ddi
diendung
1a
titiy khi
dien dung cfia"tr; tf,ng l6n
i
ra"
irri
<sub>"o"g </sub>
sudt cria mach
k#;Hi
.nhung cudng d0 dbng diOn rhi
w6ng
pha vdi ntrau. Cia tri-cria
<sub>\n</sub>
A.50
O
B.
100
o
<sub>c.200 </sub>
o
<sub>D. </sub>
<sub>3000</sub>
CAu 45: Ivtpch
nrc
n6i tii5p <sub>gom cudn ddy thuAn cdin c6 </sub>
<sub>L </sub>
<sub>= </sub>
?n,
<sub>,o </sub><sub>dipn </sub><sub>c6 </sub><sub>C </sub>
<sub>= </sub>
l0-+
F
vi
bitin rr& R."
Edt
vio
hai dAu doan hiQu <sub>dien thd xoay chiAu </sub>
<sub>(100v </sub>
<sub>- </sub><sub>sqFlz) </sub>
"dth:yaoi
n
d6 m4ch
ro
.J.p
: Ji
tz.Giri
tri
cria
K Knl qo la
A.
50
f,
<sub>B. </sub>
<sub>100 </sub>
o
<sub>c. </sub>
<sub>150 </sub>
<sub>f) </sub>
D .20A
A
Ciu-46:
Tren dfY
clng
hai ddu gifl ch6t dang c6 s6ng dung. Kdt
lu{n
ndo sau day 11 dring
khi
n6i vd pha cria
dao d6ng c6c didm rrOn dAy
A'
C6c <sub>didm tr€n day ludn dao ddng </sub>
<sub>c[ng </sub>
pha
<sub>ts. </sub>
!_69 didm tr€n day luon dao d6ng kh6c pha
A tyt {P
u'
uac drcnx ffen cDng mOt bung dao ddng cfing
pha
D. Hai bung kd rrtrau luon dao
don!ruonfprra
Cfrw 47: Phdt bi6u ndo sau Aay-fa dring ?
A. Ce 6nh sing
vi
s6ng 6m trong kh6ng k*ri dAu
Ii
s6ng
ngang-B. Trong khdng khi s6ng Sm ld s6ng doc, rlnh sring
Ii
s6nfngang
C. Ce
'inh sSng vd "5ng Am rrong kirdng ichi dAu lA s6ng d-Ac
-D.
ca
6nh sring
vi
song sic* am dAu <sub>truyen duqc trong </sub>
<sub>chin </sub>
<sub>kh6ng</sub>
C6u 48: Trong thi nghiQm giao thoa tr€n mpt nudc, hai ngudn
#i
rrqp
A
vi
ts; dao d6ng ctrng pha
vdi
tAn s6
f =Zawz;
Arl
=
8cm.
Biiit
t6o dQ truydn s6ng tr6n
mft
nuJc
Ii
3-09md Mqt dudng h-dn e6 <sub>r6rn t4i rrung ditim</sub>
o
cria
AB,
nirn
trong rn6t phSng chfta
cilcian
giao thoa, b6n
kfnh
3,2
r'*.
sO aicm dao d6ng cgc dai tr6n
duong trdn
li
A.
16.
<sub>B. </sub>
18.
<sub>c. </sub>
<sub>19. </sub>
<sub>. </sub>
D.20.
cau
49: Mqt day dnn hdi
AB
dni 80 sm c6_dAu
n
ci5 dinh, dAu
A
mie vio
rnQt nh6nh pm rhoa dang dao dQng
v6i f = 50 Hz.
Khi
dm thoa rung, tr6n ddy c6 s6ng drmg
vdi
4 bgng song.
vpn
i6c't*yen
s6ng tr6n d6y ld:
A.
v:10
m/s.
<sub>B. </sub><sub>v </sub>
=
15
m/s.---.
i.
;=
2g-rnls_
C6u 5S:
i{ai
ngudn <sub>s6ng trOn rnar </sub><sub>nridc </sub>
<sub>le </sub>
<sub>Sr, </sub><sub>S, </sub><sub>ci4ch </sub><sub>nhau </sub><sub>S,S, </sub>
=
7t,
ph6t
ra
hai
s6ng
c6
pto*g1rinf,
u, = asinctt
ld
or=
acosot. s6ng khong suy gi6m. Didm
M
tr6n trung truc cfia -{,sr, gdn nh6t, cd dao dong
cDng pha vdi dao d6ng ph6r ra & ngudn-S
,c6chS,
mOt khoAng
li
A.
2B)"
/g
<sub>E. </sub>
<sub>331./8</sub>
<sub>c.381"/8</sub>
**'F H6t
{.**
</div>
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