a short linear object of length "b" lies along the principal axis of a concave mirror of focal length "f" at a distance 'u' from the pole of the mirror.What is the size of the image?
Let AB be the object and P be the pole.
Let the image be A'B'.
PA' and PB' can be found using the standard formula.
The length of the image = \(\left| {PA' - PB'} \right|\)