When a force of 15 newtons is applied to a stationary chair, it starts moving. What can you say about the frictional force between the chair and the floor of the room?

Question

anonymous · Answer

Are you given the weight of the chair?

anonymous · Answer

no

anonymous · Answer

You can say that the frictional force is just slightly less than 15 newtons. meaning ~14.9 N because 15 N overcame the force of friction. If the force of friction was 15N and 15 N was applied, then the chair wold not move.

anonymous · Answer

so no friction?

anonymous · Answer

no there is friction. and because you applied 15 N of force, and the chair moved, that means that the force of friction was less than 15 N. And by the sounds of this question, the chair just started moving at 15N, meaning that the force of friction is slightly less than 15N, presumably somewhere around 14.9N

anonymous · Answer

does that make sense?

anonymous · Answer

I'm not 100% on this but here goes.

As dave0616 said, the chair is on the ground, currently in a fixed position. When force is applied on to the chair, the ground acts as a friction force on the chair. If there were no friction force, then the chair would simply slide endlessly. Sorry if this doesn't make any sense. I'm simply trying to explain that friction is present.

anonymous · Answer

it means that frictional force is slightly less than 15 N of force.