Using a horizontal force of 200N, we intend to move a wooden cabinet across a floor at a constant velocity. What is the friction force that will be exerted on the cabinet?

For an object to move with constant velocity, the net external force experienced by it must be equal to ZERO i.e., Fexternal = 0. Thus, a friction of 200N must be exerted on the cabinet so that it moves with a constant velocity under the applied horizontal force of 200N.