How Do Galileo Thermometers Work?
The colored floating spheres are pushed either up or down depending on the changing density of the clear fluid inside the glass thermometer body. When the temperature goes up, the clear fluid becomes less dense and rises, forcing the spheres down one by one. When the temperature goes down, the clear fluid becomes denser, forcing the spheres upward. The Galileo Thermometer works due to the principle of buoyancy. Buoyancy determines whether objects float or sink in a liquid and is responsible for the fact that even boats made of steel can float. The only factor that determines whether a large object will float or sink in a particular liquid relates the object’s mass to the mass of the liquid displaced by the object when submerged. If the object’s mass is greater than the mass of liquid displaced, the object will sink. If the object’s mass is less than the mass of liquid displaced, the object will float. In the Galileo Thermometer, the small glass bulbs are partly filled with a different
