you push a 20kg box on a wooden floor, downward to the right at an angle of 60degrees to the vertical, with a constant speed of .5m/s. The coefficient of the friction between the floor and the box is 0.7.
a. How hard did you push the box?
b. You pushed a distance of 50m. How much work did you do?
c. How much work did the other forces do?
d. What is work done by all the forces? Is the result consistent with energy principle?