A thin liquid convex lens is formed in glass .Refractive index of the liquid is 4/3 and that of glass is 3/2.If 'f' is the focal length of the liquid lens in the air, its focal length and nature in the glass is?what is the formula used?
1) f,convex
2) f,concave
3)2f,concave
4) 3f,concave
