Question

how can we determine the position of the image in a lens

Answer 1

Ray tracing is used to locate the image formed by a lens. Rays originating from the same point on the object are traced—the three chosen rays each follow one of the rules for ray tracing, so that their paths are easy to determine. The image is located at the point where the rays cross.

Answer 2

To determine the position of the image, two equations are generally used:
The Newtonian Image Equation describes the position of the bject and the image relative to the focal points of the lens.

☺The Gauss-equation describes the positions of the object and the image relative to the principal points.
☺The lens equation.



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