Fowler Sandoval

06/17/2024 · High School

Our discussion of the liquid thermometer made use of one of the best-known changes that occur in most substances: As temperature of the substance increases, its volume increases. This phenomenon, known as thermal expansion, plays an important role in numerous applications. Thermal expansion joints, for example, must be included in buildings, concrete highways, and bridges to compensate for changes in dimensions with variations in temperature (Fig. 10.8 on page 338). The overall thermal expansion of an object is a consequence of the change in the average separation between its constituent atoms or molecules. To understand this idea, consider how the atoms in a solid substance behave. These atoms are located at fixed equilibrium positions; if an atom is pulled away from its position, a restoring force pulls it back, We can imagine that the atoms are particles con- nected by springs to their neighboring atoms. (See Fig, 9.1 in the previous chap- ter.) If an atom is pulled away from its equilibrium position, the distortion of the springs provides a restoring force.