Question

A box is pushed down at an angle of 32 degrees on a rough surface. The box moves to the right.

A picture of a woman pushing downward at an angle of 32 degrees with the horizontal on a box. There is a dot in the center of the box and a force pointing southeast away from it labeled F Subscript p.

What equation should be used to find the net force in the y-direction?

F subscript net, y = F subscript N minus F subscript g.
F subscript net, y = F subscript p minus F subscript f.
F subscript net, y = F subscript N minus F subscript g minus F subscript p cos(32).
F subscript net, y = F subscript N minus F subscript g minus F subscript p sin(32).

Answer 1

F_net,y = F_N − F_g − F_p sin(32)

Reason: the push is 32° below the horizontal, so its vertical component is downward with magnitude F_p·sin(32). Taking up as positive gives F_N (up) minus weight and minus that vertical push component.