Real Depth And Apparent Depth - Practice Questions & MCQ

Real depth and Apparent depth

Case 1.  When object is in denser medium and observer is in rarer medium.

If object and observer are situated in different medium then due to refraction, object appears to be displaced from it's real position.

Here O is the real position of the object and O' is the apparent position of the object as seen by the observer. 'h' is the real depth of the object from the surface of the water and  h' is the apparent depth of the object.   is the density of the medium where the object is placed.   is the density of the rarer medium.

$
\frac{\mu_2}{\mu_1}=\frac{\text { Real depth }}{\text { Apparent depth }}=\frac{h}{h^{\prime}}
$

Therefore Real depth > Apparent depth.

Apparent shift:

$
d=h-h^{\prime}=\left(1-\frac{\mu_1}{\mu_2}\right) h
$
 

Case 2.  Object is in rarer medium and observer is in denser medium.

$
\frac{\mu_2}{\mu_1}=\frac{\text { Apparent depth }}{\text { Real depth }}=\frac{h^{\prime}}{h}
$

Therefore apparent depth > real depth.
Apparent shift:

$
d=\left(\frac{\mu_1}{\mu_2}-1\right) h
$