FAQ on Friction – JEE Mains 2017


Central Board of Secondary Education (CBSE) conducts the JEE (Joint Entrance Examination) every year. It is a platform to provide admission to the aspiring candidates across the country, into the prestigious technical colleges of our country. Candidates must work tirelessly with intensive hard work and focus for obtaining success in this examination. Physics can be one of the easiest subjects to score good marks in the famed JEE. The questions asked in physics are meant to test your knowledge of the subject and might strain you more as compared to the questions asked in chemistry or mathematics. A few important chapters and some concepts are highly significant as there is a pattern in which these questions repeat every year. Going through these questions will give you a fair idea about your preparation status and help you to utilize the remaining time before the examination. At this moment you should focus on selective study and go through the important topics.

Important Topics in Friction

Friction does fall under the important topics, which help you in scoring for JEE. Following are the concepts that should be studied carefully:

  • Concepts of friction – What it is? How it affects us?
  • Causes of friction
  • Types of friction – static friction, kinetic friction, rolling friction, fluid friction
  • Cause and direction of rolling friction
  • Coefficient of friction, angle of repose, angle of friction
  1. How to Approach a question in Friction
  2. What is the difference between static friction and kinetic friction?

Static friction is the force of friction acting between two surfaces so long as there is no relative motion between them and it is always equal to the applied force while kinetic friction is the force of friction that comes into play between two surfaces when there is some relative motion between them.

Books for reference for Friction

Refer NCERT for class 12 this book contains all the details in a very precise manner. A quick view of this can help you to understand the fundamental concepts and their applications. The important points are neatly mentioned in the book and hence it is the most student-friendly book. Some other important reference books include books by H.C.Verma and I.E.Irodov.

Practise This Question

The general day to day activities of a primary school going teen named Swami are mentioned below.
1. To walk through a waterlogged area, Swami shortens the length of his dress by folding it.
2. In school, he drew an apple in his slate with chalk.
3. After school, he came directly came back to his home and started playing with his new toy, but accidently it broke.
4. At night, his mother cooked food for him. He ate and then retires to bed.
Connect the above excerpts to reversible or irreversible change.