問題詳情
42. A converging glass lens with a refractive index of 1.5 is placed in water with a refractive index of 1.25. How many times offocal length of the lens will be changed in water?
(A) 0.3
(B) 0.8
(C) 1.5
(D) 2
(E) 2.5
參考答案
答案：E
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)