A plane monochromatic light wave falls normally on a diaphrapm with tw...
D = 10 cm = 1 m
d = 2.5 mm = 2.5 x 10
-3 m
t = 10 x 10
-6 m , n = 1.5
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A plane monochromatic light wave falls normally on a diaphrapm with tw...
D = 10 cm = 1 m
d = 2.5 mm = 2.5 x 10
-3 m
t = 10 x 10
-6 m , n = 1.5
A plane monochromatic light wave falls normally on a diaphrapm with tw...
To solve this problem, we can use the concept of interference of light waves. When light passes through two narrow slits, it creates an interference pattern on a screen.
Without the glass plate covering one of the slits, we have a double-slit interference pattern. The interference pattern consists of bright fringes (maxima) and dark fringes (minima). The bright fringes are formed where constructive interference occurs, while the dark fringes are formed where destructive interference occurs.
When one of the slits is covered by a glass plate, it introduces a phase difference between the waves passing through the two slits. This phase difference leads to a shift in the interference pattern.
The phase difference introduced by the glass plate can be calculated using the equation:
Δφ = (2π/h) * h,
where h is the thickness of the glass plate.
In this case, h = 10 mm = 10^-2 m.
Δφ = (2π/10^-2) * 10^-2
Δφ = 2π
The phase difference Δφ of 2π corresponds to a shift of one fringe. Therefore, the fringes will be displaced by a distance corresponding to the wavelength of light.
The distance between adjacent fringes (displacement) can be calculated using the equation:
δx = λ * I / d,
where λ is the wavelength of light, I is the distance between the screen and the diaphragm, and d is the distance between the two slits.
In this case, I = 100 cm = 1 m and d = 2.5 mm = 2.5 * 10^-3 m.
Using the equation, we can rearrange it to solve for λ:
λ = δx * d / I
Substituting the values, we get:
λ = (2π) * (2.5 * 10^-3) / 1
Calculating this, we find:
λ ≈ 0.0157 m
Therefore, the fringes will be displaced by a distance of approximately 0.0157 m (or 1.57 cm) in the direction perpendicular to the direction of the slits.