If the focal length of a spherical mirror is $20 \ cm$,what is its radius of curvature (in $cm$)?

$A$ light ray incident normally on a plane mirror suffers a deviation of

What is the radius of curvature of a plane mirror?

$A$ ray of light passing through the principal focus of a concave mirror,after reflection,travels in which direction?

Copy the figure and show the image formation with the help of rays.

You have a spherical mirror. The image of an object placed in front of the mirror is virtual. If the position of the object is changed,the image remains virtual and erect. Is the spherical mirror concave or convex?