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Question
Explain the meaning of the terms focus and focal length in case of a convex mirror, with the help of suitable ray diagram.
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Solution
Focus of a convex mirror: The focus of a convex mirror is a point on the principal axis from which, the light rays incident parallel to principal axis, appear to come, after reflection from the mirror.
Focal length of a convex mirror: The distance of the focus from the pole of the convex mirror is called its focal length.

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