a concave mirror is placed at 10 cm above the water level of a container of height 40 cm the - Science - Light - Reflection and Refraction

Question

a concave mirror is placed at 10 cm above the water level of a
container of height 40 cm the image is placed at the bottom of
container at 30 cm below the water level find the focal length when
the refractive index=1 33 cm

Ved Prakash Lakhera · Accepted Answer

When a concave mirror os placed 10cm above the water level, the image of the bottom of the container is focussed at 30cm below the water level
The image is formed at the centre of curvature of the concave mirror
Therefore the radius of curvature of concave mirror is 10+30=40cm
The focal lenghth of concave mirror=radius of curvature2=402= 20cm

a concave mirror is placed at 10 cm above the water level of a container of height 40 cm.the image is placed at the bottom of container at 30 cm below the water level.find the focal length.when the refractive index=1.33 cm