Subjects like physics are very conceptual and the CBSE exams have numerical problems to test students’ ability to apply the concepts. It is very important that the student knows the correct approach to any problem while solving the same. If the student can approach the question correctly, most of the time his steps will be right and he will get the final answer without any problems. One of the best ways to develop command over the subject is to regularly solve Physics sample paper for class 11 and Class 12 Physics NCERT solutions . The following questions illustrate what needs to be kept in mind and how to approach the question in a planned manner. A convex lens of focal length 20 cm is placed 10 cm in front of a convex mirror of a radius of 15cm. Where should a point object be placed in front of the lens so that it images on itself? When a question such as this is asked, in most cases the student starts to find the image by applying lens formulae and mirror formulae for ea...