Light from a point source in air falls on a spherical glass surface (n = 1.5 and radius of curvature = 20 cm). The distance of the light source from the glass surface is 100 cm. At what position the image is formed?

Explanation

We use the relation given by Eq. (9.16). Here

`u=-100cm, v=?, R=+20 cm, n_(1)=1, and n_(2)=1.5`
We then have
`(1.5)/(v)+(1)/(100)=(0.5)/(20)`
`or v=+100cm`
The image is formed at a distance of 100 cm from the glass surface, in the direction of incident light.