Define linear magnification of an object. Write the expression for the same.

Explanation

Linear magnification of an object specifies how large or small the image of the object formed in a spherical mirror or lens is when compared to the size of the object. Linear magnification (m) is the ratio of the height of the image (h.) to the height of the object (h) :
`m=(h.)/(h)`
Linear magnification can also be expressed as the ratio of the image distance (v) to object distance (u) :
`m=(v)/(u)`.