Question

If $u$ represents object distance from pole of spherical mirror and $v$ represents image distance pole of mirror and $f$ is the focal length or the mirror, then a straight line $u=v$ will cut $u$ versus $v$ graph at

• A. $(f,f)$
• B. $(2f,2f)$
• C. $(f,2f)$
• D. $(0,0)$

Answer 1

The correct option is B $(2f,2f)$

For a special mirror :

$\frac{1}{v}+\frac{1}{u}=\frac{1}{f}$ ......(1)

Given that straight line : $u=v$

As we know

$\frac{1}{u}+\frac{1}{v}=\frac{1}{f}⟹\frac{2}{u}=\frac{1}{f}$

$u=2f,v=2f$

Hence option B is the right answer