35.15 .. Coherent light with wavelength 600 nm passes through two very narrow slits and the interference pattern is observed on a screen 3.00 m from the slits. The first-order bright fringe is at 4.84 mm from the center of the central bright fringe. For what wavelength of light will the first-order dark fringe be observed at this same point on the screen

Respuesta :

Answer:

[tex]1.199\ \mu\text{m}[/tex]

Explanation:

[tex]\lambda[/tex] = Wavelength = 600 nm

D = Distance of the light source from screen = 3 m

y = Distance of first order bright fringe from center = 4.84 mm

d = Distance between slits

m = Order = 1

We have the relation

[tex]y=\dfrac{D\lambda}{d}\\\Rightarrow d=\dfrac{D\lambda}{y}\\\Rightarrow d=\dfrac{3\times 600\times 10^{-9}}{4.84\times 10^{-3}}\\\Rightarrow d=0.0003719\ \text{m}[/tex]

From the question we have

[tex]y=\dfrac{\dfrac{1}{2}3\lambda}{d}\\\Rightarrow \lambda=\dfrac{2}{3}yd\\\Rightarrow \lambda=\dfrac{2}{3}\times 4.84\times 10^{-3}\times 0.0003719\\\Rightarrow \lambda=0.000001199\ \text{m}=1.199\ \mu\text{m}[/tex]

The required wavelength of light is [tex]1.199\ \mu\text{m}[/tex].