A concave lens of focal length f forms an image which is n times the size of the object What is the distance of the object from the lens in terms of f and n?

Explanation

To solve the problem of finding the distance of the object from a concave lens in terms of its focal length \( f \) and the magnification \( n \), we can follow these steps:

### Step 1: Understand Magnification
The magnification \( m \) of a lens is defined as the ratio of the height of the image \( h' \) to the height of the object \( h \), or alternatively, it can be expressed in terms of the object distance \( u \) and the image distance \( v \):
\[ m = \frac{h'}{h} = \frac{v}{u} \]
Given that the image is \( n \) times the size of the object, we can write:
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