Question:
Distance between twice-magnified virtual image of an object placed in front of mirror is 15 cm. Find focal length of spherical mirror in cm.
Distance between twice-magnified virtual image of an object placed in front of mirror is 15 cm. Find focal length of spherical mirror in cm.
Updated On: Jan 13, 2026
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Correct Answer: 10
Solution and Explanation
The correct answer is :10
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Concepts Used:
Spherical Mirrors
A spherical mirror is a mirror which has been cut out of a spherical surface.
There are two kinds of spherical mirrors:
- Convex Mirror
- Concave Mirror
Concave Mirror
Concave mirrors are also called converging mirrors, because in these types of mirrors, light rays converge at a point after impact and reflect back from the reflective surface of the mirror.
Convex Mirror
The convex mirror has a reflective surface that is curved outward. Regardless of the distance between the subject and the mirrors, these mirrors are "always" virtual, upright and reduced.