First slide

In YDSE one of the slits is covered with a thin transparent sheet

Question

In a Young's double slit experiment, the fringes are displaced by a distance x when a glass plate of refractive index 1. 5 is introduced in the path of one of the beams. when this plate is replaced by another plate of the same thickness, the shift of fringes is [3/2) x. The refractive index of the second plate is

Easy

A

1.75
B

1.50
C

1.25
D

1.00

Solution

The path difference introduced by a plate of thickness f and refractive index p is given by $Δ = (μ - 1) t$ A path difference of l, introduces a phase shift of $β$ where $β = λD / (2 d)$ 2d = = separation between slits
$So, a path difference of (μ - 1) t introduces a shifts x on he screen given by x = \frac{(μ - 1) tβ}{λ} for first plate x = \frac{(μ_{1} - 1) tβ}{λ} for second plate \frac{3}{2} x = \frac{(μ_{2} - 1) tβ}{λ} ∴ \frac{(μ_{2} - 1)}{(μ_{1} - 1)} = \frac{3}{2} or \frac{(μ_{2} - 1)}{(1 \cdot 5 - 1)} = \frac{3}{2} μ_{2} = 1 .75$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App