Question

A 4-cm-thick layer of water covers a 6-cm thick glass slab. A coin is placed at the bottom of the slab and is being observed from the air side along the normal to the surface. Find the apparent position of the coin from the surface.

Answer 1

As the thick layer of water is placed over the glass slab. The coin placed beneath the glass slab will appear to shift upwards due to both glass and water by distance s. This apparent shift is thus given by