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A ray of light travelling in air has wavelength λ, frequency n, velocity v and intensity I. If this ray enters into water then these parameters are λ', n', v' and I' respectively. Which relation is correct
A
$\lambda = \lambda'$
B
n = n'
C
v = v'
D
I = I'
Detailed Solution
When light passes from one medium to another, its frequency remains unchanged, because the frequency is set by the source.
Speed decreases in water ($v' = \dfrac{v}{\mu}$), and so does the wavelength ($\lambda' = \dfrac{\lambda}{\mu}$).
Some light is reflected at the surface, so the intensity also decreases.
So the correct relation is n = n'.
Speed decreases in water ($v' = \dfrac{v}{\mu}$), and so does the wavelength ($\lambda' = \dfrac{\lambda}{\mu}$).
Some light is reflected at the surface, so the intensity also decreases.
So the correct relation is n = n'.