An object is placed at a distance of $25 \, cm$ away from a converging mirror of focal length $20 \, cm$. Discuss the effect on the nature and position of the image if the position of the object changes from $25 \, cm$ to $15 \, cm$. Justify your answer without using the mirror formula.

(N/A) converging mirror is a concave mirror. The focal length $f$ is $20 \, cm$.
Initially,the object is at $25 \, cm$,which is between the center of curvature $(C = 40 \, cm)$ and the focus $(F = 20 \, cm)$. In this position,the image formed is real,inverted,and magnified,located beyond the center of curvature.
As the object is moved from $25 \, cm$ to $20 \, cm$ (the focus),the image shifts further away from the mirror and its size increases.
When the object is at the focus ($15 \, cm$ is between the focus and the pole),the image is formed at infinity.
When the object is moved from $20 \, cm$ to $15 \, cm$,it is now placed between the focus and the pole.
In this new position,the image becomes virtual,erect,and magnified,and it is formed behind the mirror.