Question

The ratio of the size of the image to the size of the object

Answer 1

Magnification of a lens is given as $m=\frac{v}{u}=\frac{h_{image}}{h_{object}}$ where,

1. Distance of the object from the optical center of the lens $=u$
2. Distance of the image from the optical center of the lens $=v$
3. Height of the image $=h_{image}$
4. Height of the object $=h_{object}$

Hence, the ratio of the size of the image to the size of the object is magnification.