I am a class 11 student , I am preparing for KVPY and I've heard Ray optics is an important chapter for KVPY but it's in class 12 , so it is not possible for me to cover whole chapter so please tell , which topics in ray optics should I study for KVPY ?
Ray optics is a fairly easy chapter, even with respect to class 12th Physics. But, some important topics include refraction, reflection and the natural phenomena. What I would suggest you to do is, look at past year KVPY questions from the chapter, and analyse for yourself. Because all the topics are related, you might have to go through everything once.