Question

A layer of benzene $({\mu }_1=1.5)6\text{cm}$ deep floats on water $({\mu }_2=1.33)4\text{cm}$ deep. When viewed vertically through air the apparent distance of the bottom of the vessel below the top surface of the benzene will be -

• A. $14\text{cm}$
• B. $7\text{cm}$
• C. $21\text{cm}$
• D. $3.5\text{cm}$

Answer 1

The correct option is B $7\text{cm}$


Actual depth $=d$
Apparent depth $=\frac{d}{n}$
Total length for benzene viewed from viewer
$=\frac{6}{3/2}=4\text{cm}$
For water $=\frac{4}{4/3}=3\text{cm}$
So, apparent depth of bottom of vessel below the surface of benzene will be
$4\text{cm}+3\text{cm}$
$=7\text{cm}$