A small pin fixed on a table top is viewed from above from a distance of `50 cm`. By what distance would the pin appear to be raised, if it be viewed from the same point through a `15 cm`. Thick glass slab held parallel to the table? `mu` of glass is `1.5`. Does the answer depend on location of the slab ?

Explanation

Given, refractive index of glass slab, `mu=1.5`,
Real depth of slab = 15 cm
We know that,
`mu=("Real Depth")/("Apparent depth")`
`1.5=(15)/("Apparent depth")`
`therefore" Apparent depth"`
`=(15)/(1.5)=10cm`
`therefore" Pin appears raised by "15-10=5cm`
The result is independent of the location of the slab.