Mumbai university > FE > SEM 2 > Applied Physics II

Marks: 3M

Year: Dec 2013

Resolving power of a diffraction grating is defined as the ration of wavelength of light

(λ) to the smallest resolvable wavelength difference (Δλ)

$R.P = \frac{λ}{Δλ}$

Thus a grating with high resolving power can distinguish between small differences in wavelength.

Mathematically,

$R.P = \frac{λ}{Δλ} = mN$

Where, m is the order of maxima

N is the order of slits

Thus by increasing the number of slits, we can increase the resolving power of the diffraction grating.