Question

In placing a thin sheet of mica of thickness 12 × 10^–5 cm in the path of one of the interfering beams in YDSE, the central fringe shifts equal to a fringe width. Find the refractive index of mica. Given l = 600 nm –

• A. 1.5
• B. 1.48
• C. 1.61
• D. 1.56

Answer 1

Answer: (A)

1.5

Answer 2

$\frac{\lambda D}{d}$ = (m _ 1) t $\frac{D}{d}$ ̃ m = $\frac{\lambda}{t}$ + 1