A `0.02 cm` wide slit is illuminated at normal incidence by light having wavelength `6 xx 10^(-7)m`.
(i) Find the width of the central band maximum on the screen which is `1 m` away from slit.
(ii) What would be the width of central maximum, if the apparatus is immersed in water whose refractive index is `4//3` ?

Answer

(i) `0.6 cm` (ii) `0.45 cm`

Explanation

(ii) Width of central band maximum on immersing the apparatus in water becomes `1//mu` time, because `lambda' = lambda//mu`