A heavy box (mass 25kg) is dragged along the floor by a kid at a 30° angle to the horizontal with a force
of 80N (which is the maximum force the kid can apply).
a. Draw the free body diagram.
b. What is the normal force FN?
c. Does the normal force decrease or increase as the angle of pull increases? Explain.
d. Assuming no friction, what is the acceleration of the box?
e. Assuming it begins at rest, what is its speed after ten seconds?
f. Is it possible for the kid to lift the box by pulling straight up on the rope?
g. In the absence of friction, what is the net force in the x-direction if the kid pulls at a 30° angle?
h. In the absence of friction, what is the net force in the x-direction if the kid pulls at a 45° angle?
i. In the absence of friction, what is the net force in the x-direction if the kid pulls at a60° angle?