Question

Assertion :The relation among $u,v$ and $f$ for the spherical mirror is valid only for mirrors whose sizes are very small compared to their radii of curvature. Reason: The laws of reflection are strictly valid for plane surfaces but not for large spherical surfaces.

• 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 C Assertion is correct but Reason is incorrect

For reflection from a spherical mirror with the aperture of mirror being very small compared to the radius of curvature of the mirror, the position of image $v$ is given by

$\frac{1}{v}-\frac{1}{u}=\frac{1}{f}$

Also the law of reflection is valid for reflection of light from any point. The angle of incidence is equal to angle of reflection for reflection from any given point. Thus Reason is incorrect.

Hence correct answer is option C.