What keeps the spiral shape in a rope from coming undone?


As in if you pull two ends of a rope the rope will pull taut, but I have difficulty understanding the mechanics of how the helical spiral doesn’t simply unwind, even at rest. I saw a how it’s made video on YouTube for rope, but I am still confused. Do note I am not asking about fraying of the ends of a rope, I am asking how the entire rope stays wound! Thanks!

In: 7

Because the individual strand is twisted in the opposite direction. This creates tension that causes it to want to untwist *into* the spiral. That, plus the ends being fused or bound in some way, keeps the rope together.

The strands of rope are twisted up. To unwind them from the main rope would require twisting the individual strands even further in the direction they were already twisted, which they resist.