An object of height $5 \, cm$ is placed at a distance of $1 \, m$ from a concave mirror having a radius of curvature of $20 \, cm$. The height of the image is ....... $cm$.

You are asked to design a shaving mirror assuming that a person keeps it $10\,cm$ from his face and views the magnified image of the face at the closest comfortable distance of $25\,cm$. The radius of curvature of the mirror would then be.....$cm$.

An object is placed at a distance of $18 \ cm$ in front of a mirror. If the image is formed at a distance of $4 \ cm$ on the other side,then the focal length,nature of the mirror,and nature of the image are respectively:

$A$ candle flame of $3 \, cm$ is placed at $300 \, cm$ from a wall. $A$ concave mirror is kept at distance $x$ from the wall in such a way that the image of the flame on the wall is $9 \, cm$. Then $x$ is......$cm$.

$A$ small candle,$2.5\; cm$ in size,is placed at $27\; cm$ in front of a concave mirror of radius of curvature $36\; cm$. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Describe the nature and size of the image. If the candle is moved closer to the mirror,how would the screen have to be moved?

$A$ concave mirror produces an image of an object such that the distance between the object and the image is $20\ cm$. If the magnification of the image is $-3$,then the magnitude of the radius of curvature of the mirror is: (in $cm$)