13. Ponyo’s Heat Tube Ponyo的热管

A glass tube with a sealed top is filled with water and mounted vertically. The bottom end of the tube is immersed in a beaker of water and a short segment of the tube is heated. Investigate and explain the periodic motion of the water and any vapour bubbles observed.

将一个玻璃管（顶部密封）中灌满水并垂直安装。玻璃管底端浸在盛有水的烧杯中，对玻璃管的一小段进行加热。研究并解释水和观察到的气泡的周期性运动。