Question

Consider the situation shown in figure. Water $({\mu }_w=\frac{4}{3})$ is filled in a breaker upto a height of 10 cm. A plane mirror fixed at a height of 5 cm from the surface of water. Distance of image from the mirror after reflection from it of an object O at the bottom of the beaker is

• A. 15 cm
• B. 12.5 cm
• C. 7.5 cm
• D. 10 cm

Answer 1

The correct option is B 12.5 cm

From figure it is clear that object appears to be raised by $\frac{10}{4}cm\left(2.5cm\right)$
Hence distance between mirror and O'=5+7.5 =12.5 cm
So final image will be formed at 12.5 cm behind the plane mirror.