A luminous object and a screen are at a fixed distance ’D’ apart. A converging lens for focal length 'f' is placed between the object and screen. A real image of the object is formed on the screen for two less positions separated by a distance’d’. The ratio of two image sizes for two positions of the lens is:
As we learn
Magnification at two position of lens -
- wherein
Mangnification at position 1 of lens.
Mangnification at position 2