Question

A point 'O' marked on the surface of a glass sphere of diameter 20 cm is viewed through glass from the position directly opposite to the point O. If the refractive index of the glass is 1⋅5, find the position of the image formed. Also, draw the ray diagram for the formation of the image

Answer 1

Point O is marked on the surface of the glass sphere, and the image of point O is being observed from point P. Let the observed distance of point O is `"d"_"observed"`, then according to the relation of apparent depth,

`"d"_"observed"/mu_"observer" = "d"_"Actual"/(mu_"Object")`

⇒ `"d"_"observed" = mu_"observer" xx "d"_"Actual"/mu_"Object"`

⇒ `"d"_"observed" = 1 xx (20"cm")/1.5  = 40/3 "cm"`

Hence the image of point O will form at`40/3` cm from the point P towards point O. The figure below shows the ray diagram.