Monochromatic light of wvalength `589 nm` is incident from air on a water surface. What are the wavelength, frequency and speed of (a) reflected and (b) refracted light ? `mu` of water is 1.33`.

Explanation

Here, `lambda = 589 nm, c = 3 xx 10^(8) m//s, mu = 1.33`
(a) For reflected light
wavelength, `lambda = 589 xx 10^(-9)m, v = ( c)/(lambda) = (3 xx 10^(8))/(589 xx 10^(-9)) = 5.09 xx 10^(14)` hertz
Speed, `v = c = 3 xx 10^(8)m//s`
(b) For refracted light `lambda' = (lambda)/(mu) = (589 xx 10^(-9))/(1.33) = 4.42 xx 10^(-7)m`
As frequency remains unaffected on entering medium, therefore, `v' = v = 5.09 xx 10^(14)` hertz
speed, `v' = ( c)/(mu) = (3 xx 10^(8))/(1.33) = 2.25 xx 10^(8)m//s`