Bob is pushing a box across the floor at a constant speed of 1.3 m/s, applying a horizontal force whose magnitude is 75 N. Alice is pushing an identical box across the floor at a constant speed of 2.6 m/s, applying a horizontal force.

(a) What is the magnitude of the force that Alice is applying to the box?

F =  N

(b) With the two boxes starting from rest, explain qualitatively what Alice and Bob did to get their boxes moving at different constant speeds.Each initially applied a force bigger than static friction to get the box moving and accelerating, then when the desired final speed was achieved they reduced the force to make the net force zero.

In order to keep the box moving twice as fast, Alice had to apply a constant force that was twice as large as the force that Bob applied.