In a Young's double-slit experiment, a thin film of thickness t and refractive index μ is placed in front of slit A. If β is the fringe width, choose the correct statement(s) about the shift of the central maximum.
Select all that apply

Question

In a Young's double-slit experiment, a thin film of thickness t and refractive index μ is placed in front of slit A. If β is the fringe width, choose the correct statement(s) about the shift of the central maximum.

Select all that apply

G1 Physics · Accepted Answer

The film before slit A adds optical path Δ=(μ−1)t. The central fringe shifts toward slit A. Its magnitude is y=ΔD/d=(μ−1)tD/d. Since β=λD/d, y=(μ−1)tβ/λ. Correct: A,C.