Define the centre of curvature for a convex mirror.

$A$ spherical mirror is obtained as shown in the figure from a hollow glass sphere. If an object is positioned in front of the mirror,what will be the nature and magnification of the image of the object? (Figure drawn as schematic and not to scale)

The focal length $f$ is related to the radius of curvature $R$ of a spherical convex mirror by

Suppose while sitting in a parked car,you notice a jogger approaching towards you in the side view mirror of radius of curvature $R = 2 \; m$. If the jogger is running at a speed of $5 \; m s^{-1}$,how fast does the image of the jogger appear to move when the jogger is $(a) \; 39 \; m$,$(b) \; 29 \; m$,$(c) \; 19 \; m$,and $(d) \; 9 \; m$ away?

The direction of a ray of light incident on a concave mirror is shown by $PQ$, where $PQ$ is parallel to the principal axis. The direction in which the ray would travel after reflection is shown by four rays marked as $A$, $B$, $C$ and $D$. Which of the four rays correctly shows the direction of the reflected ray?

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 ........ $cm$.