This preview shows page 1. Sign up to view the full content.
Unformatted text preview: 330 CHAPTER 24 24.60 Assuming the glass plates have refractive indices greater than that of both air and water, there will be a phase reversal at the reflection from the lower surface of the film but no reversal from reflection at the top of the film. Therefore, the condition for a dark fringe is ( ) 2 n film t m m n λ λ = = for 0, 1, 2, m = … m If the highest order dark band observed is 84 = (a total of 85 dark bands counting the order at the edge of contact), the maximum thickness of the wedge is m = max max 84 2 2 film m t n 42 1.00 λ λ λ = = = When the film consists of water, the highest order dark fringe appearing will be ( ) max max 2 2 42 film n m t = = 1.333 λ λ λ 112 = Counting the zeroth order, a total of 113 dark fringes are now observed. 24.61 With n n , there is a 180° phase shift in light reflecting from each surface of the oil film. In such a case, the conditions for constructive and destructive interference are reversed film....
View Full Document
This note was uploaded on 12/09/2011 for the course PHYS 2020 taught by Professor Staff during the Fall '10 term at FIU.
- Fall '10