# When the person in a cartoon steps inside a loop of a rope on the ground and onto a trap, and the rope grabs the ankle so quickly and lift up high to raise the person upside-down and hanging? How does this work in real life?

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When the person in a cartoon steps inside a loop of a rope on the ground and onto a trap, and the rope grabs the ankle so quickly and lift up high to raise the person upside-down and hanging? How does this work in real life?

In: Physics

The knot in the rope is tied such that it allows the rope to pass through it without any issue. So when the rope is tightened by the trap mechanism it will first just pull the rope through the knot making the noose tighter. When the noose tightens over the foot the same pulling of the rope will be used to lift the person into the air. The more you pull the tighter it will be so in order to release the noose from the foot you need to release tension on the rope. But this can be quite hard when you are dangling in the air. This type of trap is quite hard to make to work so it is very rarely used in practice. But it looks great in cartoons.

Depends on how the trap is set. Basically any trap work on the concept of trigger. Somewhere is a trigger that, when triggered activate the trap. Some are more complex than others.

For the old rope trap, the trigger is usually in the middle of the rope. If you walk in the trap, you push the trigger and the trap activate.

It’s called a “snare trap”. You can google that to get a diagram for how they work. Basically, you store tension in a rope by bending a tree branch back, securing it with a fragile trigger, and then having loop that will tighten when the end is pulled. If something disturbs the loop or rope, the fragile trigger gets loose, the branch pulls on the rope, and the loop then closes around whatever disturbed the loop.

If you run the tense rope over a tall tree branch too, it will lift whatever it ensnares into the air. But really, if you’re using snare traps to small animals, just getting them caught in a loop is usually enough. There’s no need to hoist them into the air.

General idea,

The loop is attached to a down-bent tree. When you step in the loop, you don’t *just* step in the loop, you also step on…something else.

The something else is a mechanism that lets the tree loose again, so that it once again snaps up in the air. And pulls the loop that catches your feet in the process.

Everyone here has explained it really well, but it still might be easier to watch a video. This guy demonstrates exactly what you’re asking in the first minute and a half.

https://youtu.be/fOZK_dlZO4E