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In a certain spectrum produced by a glas...

In a certain spectrum produced by a glass prism od dispersive power `0.031`, it was found that `mu_(r ) = 1.645 and mu_(b) = 1.665`. What si the refractive index for yellow colour ?

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Here, `omega = 0.031 , mu_(r) = 1.645 mu_(v)= 1.665, mu_(y) = ?`
`because omega=(mu_(v)-mu_(r))/(mu_(y)-1) = therefore mu_(y)-1 = (mu_(v) - mu_(r))/(omega) = (1.665-1.645)/(0.031) = (0.020)/(0.031) = 0.645 therefore mu_(y) = 0.645+1 = 1.645`
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