Question

Find the angle for the third-order maximum for 591 nm wavelength light falling on a diffraction grating having 1460 lines per centimeter.

Answer 1

15.32°

Step-by-step explanation:

We have given the wavelength
`\lambda =591nm=591* 10^(-9)m`

Diffraction grating is 1460 lines per cm

So
`d=(10^(-2))/(1460)=6.71* 10^(-6)m` (as 1 m=100 cm )

For maximum diffraction

`dsin\Theta =m\lambda` here m is order of diffraction

So
`6.71* 10^(-6)sin\Theta =3* 591* 10^(-9)`

`sin\Theta =0.264`

`\Theta =15.32^(\circ)`