2023 · Q3
A concave mirror of radius of curvature 50 cm is used to form an image of an object kept at a distance of 25 cm from the mirror on its principal axis. What will be the position of the image from the mirror?
General KnowledgePhysics
- AAt infinity
- BAt 50 cm
- CAt 25 cm
- DAt 75 cm
Explanation
For a concave mirror the focal length is f = R/2 = 50/2 = 25 cm. The object is placed at 25 cm from the mirror, i.e., exactly at the principal focus. Rays starting from the focus emerge parallel after reflection from a concave mirror, so the reflected rays meet only at infinity and the image forms at infinity.