Time taken by light to cross a glass slab of thickness 4 mm and refractive index 3 is

If mirrors are inclined to each other at an angle of 90°, the total number of images seen for a symmetric position of an object will be

In case of a convex mirror, the image formed is

A glass slab is placed in the path of a beam of convergent light. The point of convergence of light

For a person seeing an object placed in optically rarer medium,

Light travels from a medium of refractive index ${\mu }_1\backslash mu\_1$ to another of refractive index ${\mu }_2\backslash mu\_2$ ( ${\mu }_1\backslash mu\_1$ > ${\mu }_2\backslash mu\_2$ ). For total internal reflection of light, which is NOT true?

Optical fibre is based on which of the following phenomenon?

Commonly used glass have refractive index of 1.5. What is the critical angle for such glass?

If the critical angle for the material of a prism is C and the angle of the prism is A, then there will be no emergent ray when

Chromatic aberrations is caused due to