A concave mirror has radius of curvature 2 m. Light from a distance star is incident on the mirror. The distance of the image of the star from the mirror is:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 1 m
A star is so far away that its rays reach the mirror parallel to the principal axis. A concave mirror brings parallel rays to its principal focus, so the image forms at the focus.
\( \displaystyle f = \frac{R}{2} = \frac{2\,\mathrm{m}}{2} = 1\,\mathrm{m} \)
So the image of the star is 1 m from the mirror.