A thin mica sheet of thickness 2 × 10-6 m and refractive index (μ = 1.5) is introduced in the path of the light from upper slit. The wavelength of the wave used is 5000 mathringA. The central bright maximum will shift

Question

A thin mica sheet of thickness 2 × 10-6 m and refractive index (μ = 1.5) is introduced in the path of the light from upper slit. The wavelength of the wave used is 5000 mathringA. The central bright maximum will shift (A) 2 fringes upward (B) 2 fringes downward (C) 10 fringes upward (D) none of these

Tardigrade Admin · Accepted Answer

On introducing mica sheet,
fringe shift

= \frac{β}{λ} (μ - 1) t

where t is the thickness of sheet

∴

Fringe shift

= \frac{β}{( 5000 \times 1 0 ^{- 10} )} \times (1.5 - 1) \times (2 \times 1 0^{- 6}) = 2 β = 2 β

So, central bright maximum will shift 2 fringes upward.

Q. A thin mica sheet of thickness 2×10−6m and refractive index (μ=1.5) is introduced in the path of the light from upper slit. The wavelength of the wave used is 5000A˚. The central bright maximum will shift

2 fringes upward

2 fringes downward

10 fringes upward

none of these

On introducing mica sheet, fringe shift =λβ​(μ−1)t where t is the thickness of sheet ∴ Fringe shift =(5000×10−10)β​×(1.5−1)×(2×10−6)=2β=2β So, central bright maximum will shift 2 fringes upward.

Q. A thin mica sheet of thickness $2 \times 1 0^{- 6} m$ and refractive index $(μ = 1.5)$ is introduced in the path of the light from upper slit. The wavelength of the wave used is $5000 \overset{˚}{A}$ . The central bright maximum will shift

On introducing mica sheet,
fringe shift $= \frac{β}{λ} (μ - 1) t$
where t is the thickness of sheet
$∴$ Fringe shift $= \frac{β}{( 5000 \times 1 0 ^{- 10} )} \times (1.5 - 1) \times (2 \times 1 0^{- 6}) = 2 β = 2 β$
So, central bright maximum will shift 2 fringes upward.