C. qua B; Á
phla Nam Khi do vecto cadng dQ di)n
tradng cd
Ạ dO ton cryc dqi vd hr6ng vd phia Tdỵ
B. dO lon cwc dqi vd hadng vi phia D6ng. C. dO ton cryc dqi vd habng vi phia Bdc.
D. d0 lon bdng kh6ng.
Hwdmg đn- Chtt f ring khi i c,4 d,.1 lr.tr cuc
+
,'-i thi E cing c6 dQ 16n ctt(: rrs; ,:l l;a -,'r,:to
,-,E,8 tao thdnh m6t fari di6n liur*n" i;ecto
)
E c6 phuong vu6ng g6c vdi mdt rrhSng chria
-))
v vit B, c6 chi6u theo quy tbc vfln nrit chaị
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Quay c5i vfln nrit chai theo chi6u tir B dOn v theo g6c nho nh6t thi chiOu ti6n cira c6i vfln
-)
nrit chai ld chi6u cita vecttv Ẹ Tt d6 ta th6y
Jvecto E c6 chi6uhu&ngv0phiaTAỵ vecto E c6 chi6uhu&ngv0phiaTAỵ D6p 6n A tliing. [1 t2 12 (2) 12 12 (1)
Ciu 4. Trong thi nghiQm Y-ang vi giao thoa
anh sdng, ,gu6n sdng phat ra anh sang don
:, ,,
sdc' co bróc song ),. Tren mdn quan sdt, tAn
doan thdng A/N đi 20cm (vu6ng goc vbi hQ
van giao thoa) co 10 vdn tu;i, M vd ltr ld vi tri
cua hai vdn sang. Thay anh sdng tAn bing
:)
anh song dctn sac co bróc song )1 :l)t rhi
J
tqi M ld vi tri ctia m6t van giao thoa, so van
sdng trAn doan MIV lilc ndy la
Ạ 5. B. 6. C.7. D.8.
Iltaing đn. TrAn doan MN c6 10 vdn tOi me
Mvd N ld hai v6n s6ng, n6n tr6n doan ndy c6 11 vAn s6ng. Vi vdy tr6n daan MN c6 10
khoing vdn s6ng, m6i khoeng h 2cm. Ta c6
kho6ng v6n shD s10 SUY fa lt : -lt = -Cm. á JJ
VQy s6 khodng vAn sdng tr€n MNbitg
# = 6.
3
TrCn doan ltfiii co 7 vdn s6ng.
D6p 6tr C dirng. tr