Galileo Thermometer

Material:

• Galileo Thermometer

Big Picture:

The small glass bulbs being contained inside of Galileo Thermometer are partly filled with different-colored liquids. Although their different colors are only utilized for decoration, they merely function as fixed weights. Once the bulbs are sealed inside, their effective densities are adjusted by means of the metal tags hanging beneath them (the red bulb represents 80°F, the blue bulb represents 76°F, the orange bulb represents 72°F, the green bulb represents 68°F, and the purple bulb represents 64°F). The clear liquid in which the bulbs are submerged in is hydrocarbon, not water, because its density varies with temperature more than water does. This change of density in the liquid, along side with temperature change, causes the bulbs to rise or sink.

Principle and/or concept:

The Galileo Thermometer works on the principle of buoyancy because the object that rises or falls—the bulbs—is determining the temperature relative to the density of the hydrocarbon.

Key Words:

• Hydrocarbon is a compound of hydrogen and carbon.

Formula: