Answer:
The wavelength is 742.7 nm.
Explanation:
Given that,
Grating = 4500 lines/cm
Angle = 42°
Order number =2
We need to calculate the distance
[tex]d=\dfrac{1\times10^{-2}}{4500}[/tex]
[tex]d=2.22\times10^{-6}\ m[/tex]
We need to calculate the wavelength
Using diffraction formula
[tex]d\sin\theta=m\times\lambda[/tex]
[tex]\lambda=\dfrac{d\sin\theta}{m}[/tex]
[tex]\lambda=\dfrac{2.22\times10^{-6}\times\sin42}{2}[/tex]
[tex]\lambda=7.427\times10^{-7}[/tex]
[tex]\lambda=742.7\ nm[/tex]
Hence, The wavelength is 742.7 nm.
