In Young's slit experiment, the separation of four bright fringes is 2.5 mm when the wavelength used is 6.2×10^-7 m. The distance from the slits to the screen is 0.80 m. Calculate the separation of the two slits.
1 Answer
Solution
Given,
Slit width (d) = 0.200 mm = 0.2×10-3 m,
Distance between screen and slit (D) = 1.00 m,
Distance of 3rd bright fringe from the center (y) = 9.49 mm = 9.49×10-3 m
The wavelength of light (λ) =?
We have,
if β be the fringe width,
\(y=3\beta\)
Or, \(y=3\times\frac{\lambda D}d\)
Or, \(\lambda=\frac{y\times d}{3\times D}\)
Or, \(\lambda=\frac{9.49\times10^{-3}\times0.2\times10^{-3}}{3\times1}\)
∴ λ = 6.33×10-7 m
Hence, the required wavelength is 6.33×10^-7 m.
Topics from Physics
Physical Quantities
27
Electricity & Magnetism
48
Motion
8
Measurement
4
Electricity
166
Physical Optics
80
Waves
117
Force
51
Heat
137
Laws of Motion
1
Light
100
Pressure
139
Thermodynamics
1
Related Questions