# Torque on a block on an inclined plane

When a block is stationary on an inclined plane, the frictional force on the base of the block has a torque about the center of gravity of the block. However, the block does not rotate. Which force provides the opposing torque to that of friction? This opposing torque cannot be from gravity, since both components of the gravitational force on the block (parallel and perpendicular to the plane) pass through the center of gravity of the block and have no torque about it. Where does the opposing torque come from in order to keep the block from rotating?

• I believe that it would make more sense if don't break the weight into it's components and instead mark the resultant of the Normal reaction and friction.Then consider it's line of action.This might help you understand why the block doesn't rotate. Jun 12, 2020 at 19:40
• The normal force can provide the necessary torque. physics.stackexchange.com/questions/314729/… Jun 12, 2020 at 19:41
• But the normal force is also acting through the center of gravity of the block so it has no torque about it.
– Toba
Jun 12, 2020 at 20:11
• No, the normal force is distributed over all the surface of contact between the block and the inclined plane.
– GCLL
Jun 13, 2020 at 0:00
• But the normal forces distributed over the surface of contact sum up to give a resultant single normal force acting through the center of gravity of the body.
– Toba
Jun 13, 2020 at 1:05