Q. Which of the following is/are correctly matched?

1. Static friction – self-adjusting force
2. Sliding friction – less than limiting friction
3. Rolling friction – greater than sliding friction

Select the correct answer using the codes given below:
Answer: Only 1 & 2
Notes: Static friction is a self-adjusting force. Sliding friction is always less than the limiting (maximum static) friction. Rolling friction is the smallest frictional force, much less than sliding friction. Therefore, only statements 1 and 2 are correct, while statement 3 is incorrect.