Physics-
General
Easy
Question
Three spools A, B and C are placed on rough ground and acted by equal force F. Then which of the following statement is incorrect?
- Frictional force on spool A is in backward direction
- Frictional force on spool B is in backward direction
- Frictional force on spool C is in backward direction
- Frictional force on spool C is in forward direction
The correct answer is: Frictional force on spool C is in forward direction
For spool A, sliding tendency of point of contact is forward Þ frictional force is in backward direction For spool B, sliding tendency of point of contact is forward Þ frictional force is in backward direction For spool C, slidin7g tendency of point of contact is forward as without friction
Here a > aR so acceleration of point of contact will be in forward direction. Þ frictional force is in backward direction.
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