Question

A glass slab of thickness 4.5 cm is placed on the piece of paper on which an ink dot is marked. The refractive index of glass is 1.5. By how much distance would an ink dot appear to be raised?

Options

• 1.5 cm

• 3.0 cm

• 4.5 cm

• 6.0 cm

Answer 1

1.5 cm

Explanation:

Refractive index (n) = `"Real depth"/"Apparent depth"`

⇒ 1.5 = `4.5/(d')`

⇒ d' = 4.5 − 1.5

= 3

h = d − d'

= 4.5 − 3

= 1.5 cm