Power of a Lens and its Unit Dioptre | explained in HINDI

In this Physics (Ray Optics) video in Hindi for class 10, 12 we explained the meaning of the power of a lens and its unit dioptre (D). The power of a lens is the reciprocal of its focal length, more technically, its second principal focal length. In S.I. its unit is dioptre which is equal to per meter. So we can say that if focal length of a lens is 2 m, its power is 0.5 dioptre. 1 dioptre is equal to 1 per meter. ★★★★★★★★★★★★★★★★ Click to visit the homepage of our channel :    / @edupoint.physics   EduPoint, Dam Road, Chandil, Dist- Seraikela-Kharsawan, Jharkhand, India.