The adjacent diagram represents a glass slab of refractive index 1.5. If PA, PB, PC and PD represent the rays of light from a point P at the bottom of the block, draw the approximate directions of these rays as they emerge out of the glass slab. (sin 42° = 2/3)

The figure given below shows the experimental set up for the determination of focal length of a lens using a plane mirror.

(a) Draw two rays from the point O of the object to show the formation of image I at O itself.

(b) What is the size of the image I?

(c) A convex lens of short focal length is used in which optical instrument?

(d) The focal length of a convex lens is 25 cm. Express its power with sign.

The diagram given below shows a ray of blue, yellow and red light incident on one face of a prism.

(a) Complete the diagram to show the effect of the prism on the ray of light and to show what is seen on the screen.

(b) A slit is placed in between the prism and the screen to pass yellow light only. What will be your observation on the screen ?

(c) What conclusion do you draw from the observation in part (ii) above ?

In the figure given below, a ray of light PQ is incident normally on the face AB of an equilateral glass prism. Complete the ray diagram showing its emergence into air after passing through the prism. Take critical angle for glass = 42°

(a) Write the angles of incidence at the faces AB and AC of the prism.

(b) Name the phenomenon suffered by the ray of light at the face AB, AC and BC of the prism respectively.