Solution:
The size of the image of an object by a mirror having a focal length of is observed to be reduced to rd to its size. The object is placed at a distance of from the concave mirror and a distance of from the convex mirror.A diminished image is formed in both concave and convex mirrors.
For concave mirrors:
It is given that the focal length and magnification .
Now, the object distance is given by,
Using the mirror formula,
Hence, the object distance is from the concave mirror.
For convex mirrors:
It is given that the focal length and magnification .
Now, the object distance ‘u; is given by,
Using the mirror formula,
Hence, the object distance is from the Convex mirror.