A hemispherical glass body of radius 10 cm and refractive index 1.5 is silvered on its curved surface . A small air bubble is 6 cm below the flat surface inside it along the axis. The position of the image of the air bubble made by the mirror is seen :

Options

A. 14 cm below flat surface
B. 30 cm below flat surface
C. 20 cm below flat surface
D. 16 cm below flat surface

Answer

C

Explanation

Radius of curvature, `R = 10 cm`
`f=-5cm`
`u=-4cm`
`(1)/(u)+(1)/(v)=(1)/(f)`
`(1)/(v)=(1)/(-5)+(1)/(4)=(1)/(20)`
`v=+20cm`
Apparent height of image, `I_(1)` from plane surface of
`h=(H)/(mu)=(30)/(1.5)`
`h=20cm`
The image is formed 20 cm below the flat surface.