[" Leyonter "],[" 4.A convex lens produces a magnification of "+5." The object is "],[" placed "]

A convex lens of focal length 15 cm produces a magnification of +4 . The object is placed:

An object placed at a distance of 16cm from a convex lens produces an image of magnification m(m gt 1) . If the object is moved towards the lens by 8cm then again an image of magnification m is obtained. The numerical value of the focal length of the lens is

Magnification of a convex lens is

Find the focal length of a convex lens which produces a virtual image at 10 cm from the lens when an object is placed at 5 cm from the lens.

Find the focal length of a convex lens which produces a virtual image at 10 cm from the lens when an object is placed at 5 cm from the lens .

The magnification of an object placed it front of a convex lens of focal length 20cm is +2 . To obtain a magnification of -2 , the object will has to be moved a distance equal to