$2^{nd}$ order maxim for wavelength is $5 × 10^{-5}$ is $30^o$ Calculate no of lines or cm

Mumbai university > FE > SEM 2 > Applied Physics II

Marks: 3M

Year: May 2013

Given that :

$n = 2$

$λ = 5 × 10^{-5}$

$θ = 30^o$

$d sinθ = nλ → d = \frac{nλ}{sinθ} = \frac{2 × 5 × 10^{-5}}{sin30}$

$d = 2 × 10^{-4} cm$

No. of lines/cm = $\frac{1}{d} = 5000$