an air bubble inside a rectangular glass slab ( cuboid)appear at 2 cm from one side and 3 cm from other opposite side if the refractive index of Glass is 1. 5 what is the actual width of the glass slab
One face of a rectangular glass plate 6 cm thick is silvered. An object held 8 cm in front of the first face, forms an image 12 cm behind the silvered face. The refractive index of the glass is :