The phenomenon observed during the shower, where the flexible pipe moves erratically, is identified as "firehose instability." This behavior occurs when the fluid dynamics within the pipe create oscillations, causing it to thrash uncontrollably. The term is well-documented in fluid mechanics literature, specifically in the context of unstable flows. For further reading, refer to the detailed explanation found in the provided link to the relevant academic text.
PREREQUISITESEngineers, physicists, and students studying fluid dynamics or mechanical engineering will benefit from this discussion, particularly those interested in the behavior of flexible pipes and instability phenomena.