Object O is kept in air in fron of a thin plano convex lens of radius of curvature 10cm. It's refractive index is `3//2` and the medium toward right of plane surface is water of refractive indec `4//3` . What should be the distance x of the object so that the rays become parrallel finall?

Explanation

`(mu_(3))/(v)-(mu_(1))/(u)=(mu_(2)-mu_(1))/(R_(1))+(mu_(3)-mu_(2))/(R_(2))`
`(mu_(3))/(oo)-(1)/(x)=(1.5-1)/(10)+(4//3-3//2)/(oo)`
`(_1)/(x)=(0.5)/(10)rArr x=-20cm`