An object is placed between infinity and the pole of a convex mirror. Draw a ray diagram and also state the position, the relative size and the nature of the image formed.

Redraw the following diagrams given below in your answer book and show the direction of the light ray after refraction from the lens.

A convergent lens has a focal length of 15 cm. At what distance should an object from the optical centre of the lens be placed so that its real image is formed at 30 cm on the other side of the lens?

Draw the ray diagram and also state the position, relative size and nature of the image formed by a concave mirror when the object is placed between its centre of curvature, C and the focus, F.

Define ‘refractive index of a transparent medium.’ What is its unit? Which has a higher refractive index, glass or water?