Describe biprism experiment to find the wavelength of monochromatic light. Draw the necessary ray diagram for magnified and diminished images of virtual sources. If the difference in velocities of light in glass and water is `2.7xx10^(7)"m"//"s"`, find the velocity of light in air.
`({:("Refractive index of glass = 1.5"),("Refractive index of water = 1.333"):})`

Explanation

Numerical :
Given : `v_(w)-v_(g)=2.7xx10^(7)"m"//"s",mu_(g)=1.5,mu_(w)=1.333.`
`v_(w)=(c)/(mu_(w))`
`implies" "=(c)/(1.333)`
Again, `" "v_(g)=(c)/(mu_(g))`
`implies" "=(c)/(1.5)`
`:." "v_(w)-v_(g)=(c)/(mu_(w))-(c)/(mu_(g))`
`implies" "=c[(1)/(1.333)-(1)/(1.5)]`
`implies" "2.7xx10^(7)=c[(1.5-1.333)/(1.5xx1.333)]`
`implies" "c=323272455.1=3.23xx10^(8)"m"//"s".`