91Ó°ÊÓ

Ray $1$ is reflected via the focus point and drawn parallel to the optical axis.

Ray $2$ is reflected parallel to the optical axis after passing past the focus point (or as if emanating from the focal point if $s<f$).

Ray $3$ passes through the mirror's centre and reflects at an angle of similar magnitude on the opposite side of the optical axis.

Concave mirror

Distance object to mirror is$s=40cm.$

Focal length is localid="1649244317391" $f=20cm.$

The ray-tracing diagram is shown in Figure. A scale is placed on the optical axis. The focal point of the mirror is drawn and noted. With its base on the optical axis, the item is represented as an arrow. The three specific rays specified in the Concepts and Principles section are drawn from the tip of the arrow. The image's tip is the spot where the three rays converge.