Define the centre of curvature for a convex mirror.

$A$ rod of length $10 \text{ cm}$ lies along the principal axis of a concave mirror of focal length $10 \text{ cm}$ as shown in the figure. The length of the image is . . . . . . $\text{cm}$.

$A$ virtual image larger than the object can be obtained by

The focal length of a spherical mirror is .......

Obtain the mirror equation for the real image formed by a concave mirror.

When an object is placed $40\ cm$ away from a spherical mirror,an image of magnification $\frac{1}{2}$ is produced. To obtain an image with magnification of $\frac{1}{3}$,the object is to be moved $:$