Answer:
[tex]\lambda = 702\ nm[/tex]
Explanation:
Given,
slit width, d = 0.215 mm
slit separation, D = 4.90 m
Wavelength of the laser light = ?
Fringe width.[tex]\beta = 1.60\ cm[/tex]
Using formula
[tex]\beta =\dfrac{\lambda D}{d}[/tex]
[tex]\lambda=\dfrac{\beta d}{D}[/tex]
[tex]\lambda=\dfrac{0.016\times 0.215\times 10^{-3}}{4.90}[/tex]
[tex]\lambda = 7.02\times 10^{-9}\ m[/tex]
[tex]\lambda = 702\ nm[/tex]
Wavelength of the laser light = [tex]\lambda = 702\ nm[/tex]
