Spherical Mirrors - 3 || MIRROR FORMULA and SIGN CONVENTION || in Hindi for Class 10

In this Physics video for Class 10 in Hindi we explained the mirror formula and we also explained what the sign conventions for the image formation by spherical mirrors are. Mirror formula : The sum of the reciprocals of the object distance and the image distance is equal to the reciprocal of the focal length. Sign convention : (i) The object is always placed to the left of the mirror. (ii) All distances parallel to the principal axis are measured from the pole of the mirror. (iii) All the distances measured to the right of the pole are taken as positive. (iv) All the distances measured to the left of the pole are taken as negative. (v) Distances above or below are measured from the principal axis. (vi) Distances above the principal axis are taken as positive. (vii) Distances below the principal axis are taken as negative. We also solved two numerical problems from NCERT Example 10.1 (1st part) A convex mirror used for rear-view on an automobile has a radius of curvature of 3.00 m. If a bus is located at 5.00 m from this mirror, find the position of the image. Example 10.2 (1st part) An object is placed at 25.0 cm in front of a concave mirror of focal length 15.0 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? 0:00 Introduction 1:20 Mirror formula 3:03 Sign Convention for reflection by spherical mirrors 8:43 NCERT Example 10.1 14:08 NCERT Example 10.2