At what distance from a concave mirror of focal length 20 cm should an object be placed so that:

(a) its real image is formed 20 cm from the mirror?

(b) its virtual image is formed 20 cm from the mirror?

Linear magnification (m) produced by a rear view mirror fitted in vehicles:

Between which two points of concave mirror should an object be placed to obtain a magnification of :

(a) - 3 (b) + 2.5 (c) - 0.4

If a concave mirror has a focal length of 20 cm, find the two positions where an object can be placed to give, in each case, an image twice the height of the object.

A mirror forms an image which is 30 cm from an object and thrice its height.

(a) Where must the mirror be situated?

(b) What is the radius of curvature?

(c) Is the mirror convex or concave?