12. The Soap Spiral 肥皂螺旋

Lower a compressed slinky into a soap solution, pull it out and straighten it. A soap film is formed between the turns of the slinky. If you break the integrity of the film, the front of the film will begin to move. Explain this phenomenon and investigate the movement of the front of the soap film.
将一螺旋弹簧玩具压缩后浸入肥皂溶液中，再将其拉伸使之离开肥皂溶液。在螺旋弹簧玩具的螺线间将会形成一张肥皂膜。如果你破坏了肥皂膜的完整性，肥皂膜的前端就会开始移动。试解释这一现象并探究肥皂膜前端的运动。