A ray of light is incident on a body x as shown in the diagram above. What is the refractive index of the body?

Light travels in straight lines. In which of the following is this principle manifested? I. Pinhole camera II. Formation of shadows III. Diffraction of light IV. Occurrence of an eclipse.

The image of any real object formed by a diverging lens is always

Which of the following is not self-luminous?

An object is placed on the principal axis and at the centre of curvature of a concave mirror. The image of the object formed by the mirror is