A parallel beam of monochromatic light of wavelength 450 m passes through a long slit of width 0.2 mm. find the angular divergence in which most of the light is diffracted.

Answer

A, C, D

Explanation

Most of the light is diffracted between the two first order minima. These minima occur at angle given by
`d sin theta=+- lambda`
`sin theta =+- (lambda)/(d) `
`= +-(450xx10^(-9))/(0.2xx10^(-3))`
`= +- 2.25xx10^(-3)` rad
`:.` The angular divergence `=4.5xx10^(-3) ` rad.