Question

An object is fixed at the bottom of a vessel and water is filled in the vessel upto a height of $10\, cm$. A plane mirror is placed at a height of $7\, cm$ from the surface of water in such a way that its reflecting surface faces the water. The distance of the image from the mirror is (Refractive index of water, $n=1.33$ )

• A. 7.5 cm
• B. 7 cm
• C. 14.5 cm
• D. 21.8 cm

Answer 1

Answer: (C)

According to the question

the apparent distance of object from the mirror, distance of image from the mirror, $d$
$=7\, cm\, +$ apparent depth
$\because $ Apparent depth$=\frac{\text { Real depth }}{\mu} $
$=\frac{10}{1.33} \,\,\,(\because \mu=1.33, $ given $)$
Hence, $ d=7 \,cm + \frac{10}{1.33}=14.5\, cm$