Like always, this year also the CBSE Class XII physics paper was difficult and tricky. It was a lengthy and an application based exam, making it hard for the students to complete it.
Though the Exam was from the prescribed NCERT syllabus, many failed to solve it completely as the too many things were to be answered from a single question.
A teacher at The Indian School Archana Raichandani remarked that even though the CBSE is raising the difficulty level, the students who have studied the NCERT thoroughly will not find it hard.
The paper was along expected lines according to another teacher, Nitin Jassal, teacher, Presidium School, Ashok Vihar. Giving the details of the paper structure he told that the five mark questions were direct and the 10 questions of three marks each were lengthy and application based.
Both the teachers and the students liked the value-based question that was based on the concept of a step down transformer.
The interesting value based question with a number of questions to be answered was:
A group of students, while coming from the school, noticed a box marked danger HT (high tension) 2,200 volts at a sub-station in the main street. They did not understand the utility of such a high voltage as the supply was only 220 volts. They asked their teacher this question the next day. The teacher thought it to be an important question and explained the answer to the whole class.
Answer the following questions.
1. What device is used to bring high voltage down to low voltage of AC and what is the principle of its working? 2. Is it possible to use this device for bringing down high DC voltage? Explain. 3. Write the values displayed by the students and the teacher.