有一个十分有趣的实验,即把一支实验室用温度计的水银球部分与点燃的火柴或打火机火苗接触时,就会观察到水银柱先是下降,然后急剧上升的现象。这是一个热膨胀问题,可从两方面加以讨论: 第一,温度计盛水银的玻璃球壳受热时发生热膨胀,使其内外半径R_内和R_外均增大,导致球壳内容积增大,对于固体来讲,随温度变化线膨胀和体 One very interesting experiment is that when a mercury thermometer in a laboratory thermometer is brought into contact with a ignited match or lighter flame, the mercury column first drops and then rises sharply. This is a thermal expansion problem that can be discussed in two ways: First, the thermal expansion of the glass bulb containing mercury in the thermometer when heated causes both the inner and outer radii R_ and R_ to increase, resulting in an increase in the inner volume of the shell. For solids, the line expands and changes with temperature