posted by physics .
what is the equal and opposite force the force of friction
like if a block is at rest on a table static friction is stil exerted by the table onto the block keeping it from moving
what is the equal and opposite force of this force?
Is the table tilted? then gravity is the other force. Friction force only exists if there is a force trying to move an object.
so there is no static friction when a block is just sitting there and not moving with no applied force?
no, of course not. Don't get into the question if no one is in the forest to hear the tree fall, does it make a sound.