Question

The object distance u, the image distance v and the magnification m in a lens follow certain linear relations. These are

• A. $\frac{1}{u}versus\frac{1}{v}$
• B. $mversusu$
• C. $uversusv$
• D. $mversus\frac{1}{v}$

Answer 1

The correct option is A $\frac{1}{u}versus\frac{1}{v}$

For a lens $\frac{1}{f}=\frac{1}{v}-\frac{1}{u}\Rightarrow \frac{1}{v}=\frac{1}{u}+\frac{1}{f}...\left(i\right)$
Also $m=\frac{f-v}{f}=1-\frac{v}{f}\Rightarrow m=(-\frac{1}{f})v+\mathrm{1...}\left(ii\right)$
On comparing equations (i) and (ii) with y = mx+c
On comparing equations (i) and (ii) with $\frac{1}{v}vs\frac{1}{u}$ and $mvs\frac{1}{v}$ is not linear.