Problem 4: Unsinkable Disk

“A metal disk with a hole at its centre sinks in a container filled with water. When a vertical water jet hits the centre of the disc, it may float on the water surface. Explain this phenomenon and investigate the relevant parameters.”

I. Phenomenon Demonstration

• Unsinkable Disk IYPT2022 by ЭйНШтейн https://youtu.be/Wi1K2yRbMLo
• Unsinkable disc by GetAClass – Physics in experiments https://youtube.com/watch?v=eP5_9eUjfkI

II. Books, Encyclopedia, Discussion and Forum Posts

• Introduction to Impinging Jets by LearnChemE https://youtube.com/watch?v=rjJciObMiE8
  Impinging jets https://thermopedia.com/content/872/
  

III. Research Papers

• Michelson, Irving(1969). Fluidic Jet Impingement-Analytical Solution and Novel Physical Characteristic. , 223(5206), 610-611. doi: 10.1038/223610a0

• Bolek, A., & Bayraktar, S. (2019). Flow and heat transfer investigation of a circular jet issuing on different types of surfaces. Sādhanā, 44(12). https://doi.org/10.1007/s12046-019-1226-6