The magnification of an image by a convex lens is positive only when the object is placed

Write three characteristics of the image formed by a convex lens when the object is placed at a distance greater than twice the focal length of convex lens.

Describe with the help of a ray-diagram, the size, nature and position of the image formed by a convex lens when an object is placed beyond 2f in front of the lens.

The magnification of the real images produced by a convex lens varies from one to infinity. What are the values of the distances of the object from the lens for these magnifications ?

A convex lens is placed between an object and a screen which are at a fixed distance apart for one position of the lens. The magnification of the image obtained on the screen is m_(1) . When the lens is moved by a distance d the magnification of the image obtained on the same screen m_(2) , Find the focal length of the lens.

A convex lens is placed between an object and a screen which are at a fixed distance apart for one position of the lens. The magnification of the image obtained on the screen is m_(1) . When the lens is moved by a distance d the magnification of the image obtained on the same screen m_(2) , Find the focal length of the lens.

A convex lens is placed between an object and a screen which are at a fixed distance apart for one position of the lens. The magnification of the image obtained on the screen is m_(1) . When the lens is moved by a distance d the magnification of the image obtained on the same screen m_(2) , Find the focal length of the lens.