Question

What is meant by magnification of lenses? Write it’s expression.

Answer 1

Hint
Magnification can be defined with the height of the image as well as the distance of the object. It is the ratio between height of object and height of image. It is denoted by “m” in the mathematical formula.

Complete Step By Step Solution
Let’s begin with what is Magnification. It is described as the ratio of a height of as Image to height of an object which means size of image to size of object. We can also term it as the distance of an image from the lens to the distance of an object from the lens.
So. In a formatted way. It can be written as
Magnification (m) $ = \dfrac{{{\text{Size}}\;{\text{of}}\;{\text{the}}\;{\text{Image}}}}{{{\text{Size}}\;{\text{of}}\;{\text{the}}\;{\text{object}}}}$
          $ \Rightarrow m = \dfrac{{{h_2}}}{{{h_1}}}$
Or we use distance then-
     $ \Rightarrow \;{\text{magnification}}\;{\text{(m)}}\;{\text{ = }}\;\dfrac{{{\text{Image}}\;{\text{distance}}}}{{{\text{object}}\;{\text{distance}}}}$
     $ \Rightarrow m = \dfrac{v}{u}$
Where, $v$ − Ιmage distance from the lens,
     $u$ − object distance from the lens.

Note
The Value of Magnification describes the Property of Image. Where $\left| m \right| > 1$ means enlarged and $\left| m \right| < 1$ means smaller than the object. The sign denotes the property of the same side or on the opposite side of the lens.