TS EAMCET 18-July-2022 Shift 2 Solved Paper

Given, when young's double slit experiment is performed in air, the angular fringe width is θ=0.2
=0.2×‌

π

180

‌rad
But we know that,
‌θ=‌

λ

d

[∵λ=600‌nm=600×10−9m]
d=‌

λ

θ

=‌

600×10−9

0.2×‌ π 180

‌‌
=‌

600×180×10−9

0.2×π

=‌

1.08×10−4

0.2π

m
When the entire measurement system is
immersed in water of refractive index µ=‌

4

3

, then new value of angular fringe width.
θ′‌=‌

λ

dµ

=‌

600×10−9

1.08×10−4 0.2π ×‌ 4 3

‌=‌

3×0.2π×600×10−9

1.08×4×10−6

=2.62×10−3‌rad
‌=2.62×10−3×‌

180

π

‌ degree ‌
‌=0.15‌ degree ‌
∴ Change in angular width =θ−θ′
=0.2∘−0.15∘=0.05∘