In Youngs double slit experiment, light of wavelength 6000 mathringA is used to produced fringes of width 0.8 mm at a distance of 2.5 m. If the whole appart is dropped in liquid of refractive index 1.6 then the fringe width will be :

Question

In Youngs double slit experiment, light of wavelength 6000 mathringA is used to produced fringes of width 0.8 mm at a distance of 2.5 m. If the whole appart is dropped in liquid of refractive index 1.6 then the fringe width will be : (A) 0.2 mm (B) 0.4 mm (C) 0.5 mm (D) 0.6 mm

Tardigrade Admin · Accepted Answer

In water λ is reduced to (λ/μ) so λ'=(λ/1.6) As ω =(D λ/d) propto λ (ω'/ω) =(λ'/λ)=(λ / 16/λ) or ω'=(0.8/1.6)=0.5 mm

Q. In Youngs double slit experiment, light of wavelength $6000 \overset{˚}{A}$ is used to produced fringes of width $0.8 mm$ at a distance of $2.5 m$ . If the whole appart is dropped in liquid of refractive index $1.6$ then the fringe width will be :

0.2 mm

0.4 mm

0.5 mm

0.6 mm

In water $λ$ is reduced to $\frac{λ}{μ}$
so $λ^{'} = \frac{λ}{1.6}$
As $ω = \frac{D λ}{d} \propto λ$
$\frac{ω ^{'}}{ω} = \frac{λ ^{'}}{λ} = \frac{λ /16}{λ}$
or $ω^{'} = \frac{0.8}{1.6} = 0.5 mm$

Q. In Youngs double slit experiment, light of wavelength 6000A˚ is used to produced fringes of width 0.8mm at a distance of 2.5m. If the whole appart is dropped in liquid of refractive index 1.6 then the fringe width will be :