Physics-
General
Easy
Question
Inner and outer radii of a spool are r and R respectively. A thread is wound over its inner surface and placed over a rough horizontal surface. Thread is pulled by a force F as shown in fig. then in case of pure rolling
- Thread unwinds, spool rotates anticlockwise and friction act leftwards
- Thread winds, spool rotates clockwise and friction acts leftwards
- Thread winds, spool moves to the right and friction act rightwards
- Thread winds, spool moves to the right and friction does not come into existence
The correct answer is: Thread winds, spool rotates clockwise and friction acts leftwards
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