$A$ convergent beam of light is incident on a convex mirror so as to converge to a distance $12 \, cm$ from the pole of the mirror. An inverted image of the same size is formed coincident with the virtual object. What is the focal length of the mirror? $(cm)$

Define the centre of curvature for a convex mirror.

$A$ small linear object is placed on the optical axis of a concave mirror. If the distance of the nearest end of the object from the mirror is greater than the radius of curvature,then:

An object is placed at a distance of $40 \,cm$ from a concave mirror of focal length $20 \,cm$. The image formed is . . . . . . .

An object ' $O$ ' is placed at a distance of $100\,cm$ in front of a concave mirror of radius of curvature $200\,cm$ as shown in the figure. The object starts moving towards the mirror at a speed of $2\,cm/s$. The position of the image from the mirror after $10\,s$ will be at ...... $cm$.

An object $2.5 \, cm$ high is placed at a distance of $10 \, cm$ from a concave mirror of radius of curvature $30 \, cm$. The size of the image is ........ $cm$.