While using an electric bulb for street lighting, the reflector should be a:

The radius of curvature of a concave mirror is $40 \ cm$ and the size of the image is twice that of the object. The object distance is $... \ cm$.

$A$ short object of length $L$ is placed along the principal axis of a concave mirror away from focus. The object distance is $u$. If the mirror has a focal length $f,$ what will be the length of the image? You may take $L << |u-f|$.

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 $:$

The image formed by a convex mirror is always:

An object is placed at a distance of $f$ from the pole of a convex mirror of focal length $f$. Where will the image be formed?