Which type of mirror has :

(a) positive focal length?

(b) negative focal length?

An object is placed at the following distances from a concave mirror of focal length 16 cm, turn by turn:

(a) 36 cm

(b) 32 cm

(c) 21 cm

(d) 9 cm

Which position of the object will produce:

(i) a magnified real image?

(ii) a magnified virtual image?

(iii) a diminished real image?

(iv) an image of same size as the object?

According to the "New Cartesian Sign Convention" for mirrors, what sign has been given to the focal length of:

(i) a concave mirror?

(ii) a convex mirror ?

What is the nature of a mirror having a focal length of, +10 cm ?

What kind of mirror can have a focal length of, - 20 cm ?