Longitudinal Waves. To see a animations of spherical longitudinal waves check out: In a longitudinal wave the particle displacement is parallel to the direction of wave propagation. The animation at right shows a one-dimensional longitudinal plane wave propagating down a tube.
The boiling point of a substance is the temperature at which the vapor pressure of the liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.
It is the basis of the design and operation of thermometers. As the temperature of the liquid in a thermometer increases, its volume increases. The liquid is enclosed in a tall, narrow glass (or plastic) column with a constant cross-sectional area.The increase in volume is thus due to a change in height of the liquid within the column.emperature and Thermometers. We all have a feel for what temperature is. We even have a shared language that we use to qualitatively describe temperature. The water in the shower or bathtub feels hot or cold or warm.