A crate is pulled across a level warehouse floor by a rope that makes a 30∘ angle above the horizontal. Two classmates propose the following free-body diagrams for the crate:
• Diagram X shows four forces: gravity (down), normal force (up), tension along the rope (up and right at 30∘), and kinetic friction (left).
• Diagram Y shows five forces: the same four as in Diagram X plus an additional upward “vertical component of tension.”
Which choice correctly identifies the diagram that is fully consistent with accepted free-body-diagram conventions for this situation?
a) Both diagrams X and Y are correct
b) Only Diagram X is correct
c) Only Diagram Y is correct
d) Neither diagram X nor diagram Y is correct