A convex lens of focal length ' $\mathrm{f}$ ' produces a real image ' $n$ ' time the size of the object.…
A convex lens of focal length ' $\mathrm{f}$ ' produces a real image ' $n$ ' time the size of the object. The image distance is
$\mathrm{f}(\mathrm{n}+1)$
$f(n-1)$
$\frac{\mathrm{f}}{(\mathrm{N}+1)}$
$\frac{\mathrm{f}}{(\mathrm{N}-\mathrm{l})}$
Solution
The image is real and hence inverted.
$\therefore \frac{\mathrm{v}}{\mathrm{u}}=-\mathrm{n} \text { or } \mathrm{u}=-\frac{\mathrm{v}}{\mathrm{n}}$
By lens equation, $\frac{1}{\mathrm{v}}-\frac{1}{\mathrm{u}}=\frac{1}{\mathrm{f}}$
$\begin{aligned}
& \frac{1}{v}+\frac{n}{v}=\frac{1}{f} \\
& v=f(1+n)
\end{aligned}$
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