The diagrams show the appearance of a fork when placed in front of and close to two mirrors A and B, turn by turn.

1. Which mirror is convex.
2. Which mirror is concave.

Give reasons for your choice.

The following table gives the refractive indices of a few media,

	1	2	3	4	5
Medium:	Water	Crown glass	Rock salt	Ruby	Diamond
Refractive index:	1.33	1.52	1.54	1.71	2.42

Use this table to give an example of:

1. A medium pair so that light speeds up when it goes from one of these medium to another.
2. A medium pair so that light slows down when it goes from one of these medium to another.

A ray of light is incident on a convex mirror as shown. Redraw the diagram and complete the path of this ray after reflection from the mirror. Mark angle of incidence and angle of reflection on it.

To construct ray diagram we use two light rays which are so chosen that it is easy to know their directions after reflection from the mirror. List these two rays and state the path of these rays after reflection. Use these rays to locate the image of an object placed between centres of curvature and focus of a concave mirror.

Draw ray diagrams showing the image formation by a convex mirror when an object is placed:
At infinity.

An object is placed at a distance of 40cm in front of a convex mirror of radius of curvature 40cm. List four characteristics of the image formed by the mirror.

Explain with the help of a diagram, why the convex lens is also called a converging lens.

List four precautions which a student should observe while determining the focal length of a given convex lens by obtaining image of a distant object on a screen.

Name the two types of spherical mirrors. What type of mirror is represented by the:

1. Back side of a shining steel spoon?
2. Front side of a shining steel spoon?