A traffic light hangs over an intersection on a cable. Nothing touches the light but that cable. Whatever is holding the light up, the cable is doing it.
Scenes with ropes and cables can hide one tension force or several. Spot them all with one routine.
The routine: find every stretched rope, string, cable, or chain attached to the object. Each one exerts its own tension force, pulling along its own line, toward its far end.
The traffic light first. One stretched cable is attached to it, so one tension force acts: the cable pulls the light upward, along the cable.
Now a hammock clipped to two trees. Two stretched ropes are attached to it, so two tension forces act: each rope pulls the hammock along its own line, toward its own tree.
A hanging flower basket is held by two stretched chains, both attached to the basket's rim. How many tension forces act on the basket? Enter the number.
Now a tire swing mid-push, its rope tilted. One stretched rope, one tension force: the rope pulls the swing along the tilted rope, toward the branch.
A piñata hangs from one rope that runs up over a tree limb. The rope's tension force on the piñata points:
A rope that is slack, or not attached to the object, adds nothing. Count only stretched ropes attached to the object itself.
A rowboat is tied to a dock by one taut line while the river current pushes on the hull. Which force on the boat is a tension force?
A birthday banner hangs from two strings, one taped to each end of a doorway. List the tension forces on the banner.
Count the stretched strings attached to the banner: two.
Each string pulls the banner along its own line, toward its own corner of the doorway.
Two tension forces: the left string pulls the banner up and to the left along itself, and the right string pulls it up and to the right along itself.
A wind chime hangs from a porch hook by one cord. List the tension forces on the wind chime.
One stretched cord is attached to the chime.
One tension force: the cord pulls the chime upward, along the cord toward the hook.
A stage backdrop hangs from three stretched cables, each attached to its top edge. How many tension forces do the cables exert on the backdrop? Enter the number.
A water-skier holds a taut towline that runs forward and slightly upward to the boat. The line's tension force on the skier points:
A sailboat at a dock has two lines to the dock: one pulled taut by the current, one hanging slack. Which statement counts the tension forces on the boat correctly?