【单选题】如图所示,设 s 1 、 s 2 为两相干光源发出波长为 l 的单色光,分别通过两种介质 (折射率分别为 n 1 和 n 2 ,且 n 1 > n 2 )射到介质的分界面上的 P 点,己知 s 1 P = s 2 P = r ,则这两条光的几何路程 D r ,光程差 d 和相位差 D j 分别为 [ ]
A.
D r = 0 , d = 0 , D j = 0 .
B.
D r = ( n 1 - n 2 ) r , d =( n 1 - n 2 ) r , D j = 2 p ( n 1 - n 2 ) r / l .
C.
D r = 0 , d =( n 1 - n 2 ) r , D j = 2 p ( n 1 - n 2 ) r / l .
D.
D r = 0 , d =( n 1 - n 2 ) r , D j = 2 p ( n 1 - n 2 ) r .
【单选题】听力原文:W: Things aren't what they used to be, are they? M: No, they aren't. Everything is upside down these days. People haven' t even got good manners any more. Look at the way children act. Q: What ar...