Yellow light with wavefront 0.5` mum` is air surface refraction in a medium in which velocity of light is `2xx10^(-8)m//s`. Then the wavelength of the light in the medium would be .

Explanation

`lamda_1/lamda_2=v_1/v_2`
Here, `lamda_1=0.5mu m, v_1=3 times 10^8 m//s`
`lamda_2= ? (x), v_2=2 times 10^8 m//s`
`0.5/x=(3 times 10^8)/(2 times 10^8)`
`implies x=0.33 mu m`