Скачать или смотреть image formed by convex lens when object is placed between optical centre and focus or focal length

The object AB has been placed between the optical centre C and focus F’ so that it is at a distance less than the focal length f of the convex lens.
A ray of light AD starting from the top of the object and parallel to the axis, passes through the other focus F after refraction through the lens and goes in the direction DX.
Another ray of light AC passing through the optical centre C of the lens goes straight in the direction CY.
The two refracted rays DX and CY diverge away from one another and, therefore, they cannot meet at a point on the right side to form a real image.

We produce the refracted rays DX and CY backwards (to the left side) by dotted lines.
They appear to meet at point A’ on the left side.
Thus, A’ is the virtual image of point A of the object.
To get the complete image of the object, we draw A’B’ perpendicular to the axis from point A’.
Thus, A’B’ is the complete image of object AB.
when the object is placed within the focus of a convex lens, the image formed is :
behind the object (on the left side of lens),
virtual and erect, and
larger than the object (enlarged or magnified).
if the object has to be magnified then it should be kept within at a distance of less than focal length of a convex lens.
Please note that smaller the focal length of a convex lens, greater will be its magnifying power
a convex lens of 5 cm focal length will have a greater magnifying power than a convex lens of 50 cm focal length