A small ink dot on a paper is viewed through a glass slab of thickness 10cm and refractive index 1.5. By what distance would the dot appear to be raised?

Explanation

The dot would appear to be raised through a distance d given by
d = real thickness of the slab-apparent thickness
= real thickness – `("real thickness")/( n)`
= real thickness `(-(1)/(n))`
Given that, eal thickness of glass slab `=10 cm, n=1.5`
`:.d=10 (1-(1)/(1.5))=10((1.5-1)/(1.5))=(10xx0.5)/(1.5)=3.33 cm`