A block, kept on ground, requires 10 N of horizontal force to just start moving. If we apply a force of 5 N on the block in horizontal direction, what will be the magnitude of frictional force acting on it?
The force required to just move the block is 10 N. This means that when we apply a force of 5 N on it, it will not move. Static friction will act opposite to the applied force to balance it. Hence, frictional force acting on the block will be 5 N in the direction opposite to the applied force.