... I2 v cỏch I1 28 cm B nm gia hai dõy dn, mt phng v song song vi I1, I2, cỏch I2 14cm C mt phng v song song vi I1, I2, nm ngoi khong gia hai dũng in cỏch I2 14cm D song song vi I1, I2 v cỏch I2 20 cm ... dn, mt phng v song song vi I1, I2, cỏch I2 14cm C mt phng v song song vi I1, I2, nm ngoi khong gia hai dũng in gn I2 cỏch I2 42cm D song song vi I1, I2 v cỏch I2 20 cm 3.60 Mt khung dõy trũn bỏn ... chit sut tuyt i ca nc l n 1, ca thu tinh l n2 Chit sut t i tia sỏng ú truyn t nc sang thu tinh l: A n21 = n1/n2 B n21 = n2/n1 C n21 = n2 n1 D n 12 = n1 n2 Cõu 13: Cõu no sau õy sai? Khi mt tia sỏng...