Answer:
119.42 x 10⁻³ m
Explanation:
The distance of first dark fringe from central bright spot will be equal to the width of fringe .
Fringe width = λL /w
where λ is wavelength of light, w is slit width , L is distance of screen .
So required distance
= [tex]\frac{689\times10^{-9}\times0.65}{3.75\times10^{-6}}[/tex]
= 119.42 x 10⁻³ m
The distance between the central bright spot and the first dark fringe is equal to [tex]1.19 \times 10^{-4}\;meter[/tex]
Given the following data:
Wavelength = 689 nm.
Width of slit = 3.75 micrometers.
Length = 0.65 m.
In order to determine the unknown wavelength of the laser light, we would apply the interference experiment.
In this scenario, the distance between the central bright spot and the first dark fringe would be equal and this is given by this formula:
[tex]D = \frac{\lambda L}{w}[/tex]
Where:
λ is the wavelength of light.
Substituting the given parameters into the formula, we have;
[tex]D = \frac{689 \times 10^{-9} \times 0.65 }{3.75 \times 10^{-3}}\\\\D = \frac{44.8 \times 10^{-7} }{3.75 \times 10^{-3}}\\\\D = 1.19 \times 10^{-4}\;m[/tex]
Read more on wavelength here: brainly.com/question/14702686
