Question

What is meant by dispessive power of a diffraction
grating having 5000 lines per cm is used at normal incidence. calculate the dispersive power of the grating in the second order spectrum in the wavelength region 6000 A° dúpraction grating having 5000 lines
pen
om or used af normal incidence.calculate
the dispersive power of the grating in the second
order spectrum in the Wavelength region 6000 A.​

Answer 1

Answer:

written 2.6 years ago by

gravatar for neeta.vanage neeta.vanage • 160

modified 2.6 years ago by

gravatar for Manan Bothra Manan Bothra • 30

N = 4000 line/cm, λ = 5000 x10−8, n= 3

dθdλ=n(a+b)cosθ(a+b)sinθ=nλsinθ=nλ(a+b)sinθ=Nnλ [∵(a+b)=1N]sinθ=4000×3×5000×10−8=0.6θ=36.86

cosθ = 0.80

Therefore dispersive power dθdλ=Nncosθ=15000