28.03.2023 - 06:57

# An ornamental thermometer, commonly known as a Galileo thermometer, contains a number of spheres of hollow colored glass, representing different temperatures, immersed in a column of ethanol. A particular sphere rises from the bottom to the top of the col

Question:

An ornamental thermometer, commonly known as a Galileo thermometer, contains a number of spheres of hollow colored glass, representing different temperatures, immersed in a column of ethanol. A particular sphere rises from the bottom to the top of the column of liquid when the temperature falls below the value it represents. Which statement best explains why the sphere rises when the temperature falls?

a. The density of the liquid has increased

b. The mass of the sphere has decreased

c. The pressure exerted by the liquid has decreased

d. The temperature of the sphere is different from that of the liquid

e. The volume of the gas inside the sphere has decreased

• April 10, 2023 в 07:48

The best explanation for why a particular sphere rises in a Galileo thermometer when the temperature falls below the value it represents is option (e): The volume of the gas inside the sphere has decreased.

The spheres in a Galileo thermometer contain a specific quantity of colored liquid, usually ethanol, and a small, weighted glass bulb. As the temperature around the thermometer changes, the density of the liquid inside the spheres changes, causing the bulbs to rise or sink in the liquid.

Each sphere contains a precise volume of air, and this air is sensitive to temperature changes. When the temperature around the thermometer drops, the air inside the sphere contracts, reducing its volume. This reduction in volume makes the overall density of the sphere greater than the density of the surrounding liquid. Consequently, the sphere sinks in the liquid.

On the other hand, when the temperature around the thermometer rises, the air inside the sphere expands, increasing its volume. This increase in volume makes the overall density of the sphere less than the density of the surrounding liquid, causing the sphere to float to the top.

Therefore, the best explanation for why a sphere in a Galileo thermometer rises when the temperature falls is that the volume of the gas inside the sphere has decreased.