Question

Calculate the angle for the third-order maximum of 580-nm wavelength yellow light falling on double slits separated by 0.100 mm.

Answer 1

Answer: The angle of diffraction is 0.498°

Explanation:

To calculate the angle of diffraction, we use the equation given by Bragg, which is:

$n\lambda =2d\sin \theta$

where,  

n = order of diffraction = 3

$\lambda$ = wavelength of the light = $580nm=5.80\times 10^{-7}m$    (Conversion factor:  $1m=10^{9}nm$ )

d = spacing between the crystal planes = 0.100 mm = $1.0\times 10^{-4}$       (Conversion factor:  1 m = 1000 mm)

$\theta$ = angle of diffraction = ?

Putting values in above equation:

$3\times 5.80\times 10^{-7}=2\times 1.00\times 10^{-4}\sin \theta\\\\\sin \theta = 0.0087\\\\\theta=\sin ^{-1} (0.0087)=0.498$

Hence, the angle of diffraction is 0.498°