Light which has a wavelength of 625 nm in air, enters flintglass (nglass =1.66). a) What is the speed of light in flint glass ? b) What is the frequency of this light within the glass? c) What is the frequency of this light in air? d) What will be the wavelength of this light within theglass? Light which has a wavelength of 625 nm in air, enters flintglass (nglass =1.66). a) What is the speed of light in flint glass ? b) What is the frequency of this light within the glass? c) What is the frequency of this light in air? d) What will be the wavelength of this light within theglass?
Explanation / Answer
(a) speed = c / n = 3.00 x 108 /1.66 = 1.807 x 108 m/s . (b) freq = c / wavelength = 3.00x 108 / 625 x 10-9 = 4.80 x 1014 Hz . (c) frequency is the same in air andglass 4.80 x 1014Hz . (d) wavelength in glass = wavelength in air /n = 625 / 1.807 = 345.8 nm