Light from a point source in air falls on a spherical glass surface (refractive index, μ = 1.5 and radius of curvature = 50 cm). ​

Question

Light from a point source in air falls on a spherical glass surface (refractive index, \(\mu = 1.5\) and radius of curvature = 50 cm). The image is formed at a distance of 200 cm from the glass surface inside the glass. The magnitude of distance of the light source from the glass surface is _________m.

Answer 1

Answer is : (4)

\(\frac{1.5}{2} - \frac{1}{(-u)} = \frac{(1.5 -1)}{\left(\frac{1}{2}\right)}\)

\(\frac{1.5}{2} + \frac{1}{v} = 1\)

\(\Rightarrow \frac{1}{v} = 1 - \frac{1.5}{2} = \frac{2-1.5}{2} = \frac{0.5}{2} = \frac{1}{4}\)

v = 4