Answer:
The order of maximum is [tex]n = 5[/tex]
Explanation:
From the question we are told that
The diffraction grating is k = 300 lines per mm = 300000 lines per m
The wavelength is [tex]\lambda = 630 \ nm = 630 *10^{-9} \ m[/tex]
Generally the condition for constructive interference is mathematically represented as
[tex]dsin \theta = n * \lambda[/tex]
Here n is the order maximum
d is the distance the grating which is mathematically represented as
[tex]d = \frac{1}{k}[/tex]
=> [tex]d = \frac{1}{300000}[/tex]
=> [tex]d = 3.3*10^{-6}\ m [/tex]
So
[tex]n = \frac{dsin \theta}{ \lambda}[/tex]
at maximum [tex]sin\theta = 1[/tex]
[tex]n = \frac{d}{\lambda}[/tex]
=> [tex]n = \frac{3.3*10^{-6}}{630 *10^{-9}}[/tex]
=> [tex]n = 5[/tex]
