Ray Optics and Optical Instruments Important Questions for CBSE Class 12 Physics Optical Instrument 1.Near Point (D) The minimum distance at which an object can be seen most distinctly without any strain. For a healthy normal eye, it is 25 cm. 2.Simple Microscope (Magnifying glass) It is a converging lens of small focal length. 3.Compound Microscope It consists of two … [Read more...]