The motion of a sphere moving on a rough horizontal surface changes from pure sliding (without rolling) to pure rolling (without slipping). In this process, the force of friction:

The motion of a sphere moving on a rough horizontal surface changes fr

1.	The motion of a sphere moving on a rough horizontal surface changes from pure sliding (without rolling) to pure rolling (without slipping). In this process, the force of friction:
Answer» SOLUTION :Yes. For rolling, torque is required. The weight and NORMAL reaction cannot produce any torque as they are radial. So if friction is there it will EXERT a torque, because friction acts TANGENTIAL to the moving BODY.