Calculate the speed and wvaelength of light (i) in glass (ii) in air, when light waves light waves of frequency `6 xx 10^(14) Hz`. travel from air to glass of `mu = 1.5`.

Answer

(i) `2 xx 10^(8)m//s ; 3.3 xx 10^(-7)m`
(ii) `3 xx 10^(8)m//s ; 5 xx 10^(-7)m`

Explanation

Here, `v = 6 xx 10^(14)Hz. mu = 1.5`.
(i) In glass,
speed of light , `v_(g) = (upsilon_(a))/(mu) = (3 xx 10^(8))/(1.5) = 2 xx 10^(8)m//s`
wavelength of light, `lambda_(g) = (upsilon_(g))/(v) = (2 xx 10^(8))/(6 xx 10^(14))`
`= 3.3 xx 10^(-7)m`
(ii) In air
speed of light, `v_(a) = c = 3 xx 10^(8)m//s`
Wavelength of light, `lambda_(a) = (v_(a))/(v) = (3 xx 10^(8))/(6 xx 10^(14))`
`= 5 xx 10^(-7)m`