Page 1 - Lesson note sign convention rules of sph lens
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SAI INTERNATIONAL SCHOOL

                                                       PHYSICS
                                                       CLASS X

                                 Chapter:LIGHT-REFLECTION AND REFRACTION
                                                      MODULE-32

               Sign convention for spherical lenses


                   1.  All the distances are measured from the optical center of the lens.
                   2.  The distances measured in the same direction as that of incident light are

                       taken as positive. (Right of the lens)
                   3.  The distances measured against the direction of incident light are taken as

                       negative. (Left of the lens)
                   4.  The distances measured upward and perpendicular to the principal axis are

                       taken as positive.

                   5.  The distances measured downwards and perpendicular to principal axis is
                       taken as negative.
























               Lens formula: 1/v - 1/u = 1/f, gives the relationship between the object-distance (u),

               image-distance (v), and the focal length (f) of a spherical lens.

               Linear magnification


               It is defined as the ratio of height of image to the height of object.

               It is given as m=v/u=h i/h o








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