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

(a) Which mirror is convex?

(b) Which mirror is concave ? Give reasons for your choice.

A real image of an object is to be obtained. The mirror required for this purpose is :

Consider two statements A and B given below :

A : real image is always inverted

B : virtual image is always erect

Out of these two statements :

The diagram shows a dish antenna which is used to receive television signals from a satellite. The antenna (signal detector) is fixed in front of the curved dish.

(a) What is the purpose of the dish?

(b) Should it be concave or convex ?

(c) Where should the antenna be positioned to receive the strongest possible signals ?

(d) Explain what change you would expect in the signals if a larger dish was used.

A man standing in front of a special mirror finds his image having a very small head, a fat body and legs of normal size. What is the shape of :

(a) top part of the mirror?

(b) middle part of the mirror ?

(c) bottom part of the mirror? Give reasons for your choice.