Question

Assertion :The focal length of the concave mirror is $f$ and distance of the object from the focus is $u$. The magnification of the image will be $f/u$ Reason: Magnification=$\frac{sizeofobject}{sizeofimage}$

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is D Both Assertion and Reason are incorrect

The magnification ($M$) equation relates the ratio of the image distance and object distance to the ratio of the image height ($h_i$) and object height ($h_o$).The magnification equation is stated as follows:
$M=\frac{h_i}{h_o}=-\frac{v}{u}$
where $v$ is the image distance and $u$ is the object distance