A free-body force diagram for a heavy wooden bookcase being pushed across a classroom by a student is shown below. (a) Compare the amount of force needed to push the bookcase to the amount of friction force if it is moving at a constant speed. (b) Identify one change to the bookcase or the floor that would affect the amount of force required to move the bookcase. (c) If the amount of force applied by the student is greater than the force of friction, what would you expect the bookcase to do?

Iwould sure like to answer your question but i honestly just don’t know

Answer///air resistance,drag;

W= fd
where f is an applied force and d is the distance over which it is applied. when a parachuting skydiver is at constant velocity, he is experiencing "terminal velocity", the point at which his acceleration down is canceled out by air resistance. that means that the resisting force of the air is equal to his weight, but in the opposite direction. with this, we can solve for the work done by the force.
w = fd
w = (92.0)(9.81 m/s^2) (325)
w= 2.93 x 10^5 j
the value for work in this case is positive because it is pushing up on the skydiver, who has a downward force of gravity.
therefore the answer is 2.93 x 10^5 j