Light of wavelength `6000 Å` falls on a plane reflecting surface. What are the wavelength and frequency of reflected light. If angle between incident ray and reflected ray is `60^@`, what is the angle of incidence ?

Answer

`6000 Å, 5 xx 10^14 Hz ; 30^@`

Explanation

As wavelength and frequency ramin unchanged on reflection, therefore, `lamda' = lamda = 6000 Å`
`v' = v = ( c)/(lamda) = (3 xx 10^8)/(6000 xx 10^-10)`
=`5 xx 10^14 Hz`
Now, `/_i + /_ r = 60^@`
As `/_ r = /_ i :. 2 /_i= 60^@`
`i = 30^@`.