Deluxe Handblown Glass Drinking Bird- Energy Conversion Demonstration - Colors Vary
Deluxe Glass Drinking Bird
Liquid is Blue, Green or Red
A deluxe version of the classic Drinking Bird made from hand blown glass, works using properties of thermodynamics, converting thermal energy into mechanical energy. Fluid inside condenses from the evaporation cooling of the water off the birds beak, making it top heavy and dunking it back into the water. The condensate rejoins the liquid pool in the birds bulb, and he tips up again. Process continues indefinitely. CUP NOT INCLUDED
- How he works in more technical terms: As the water evaporates, it draws heat from inside the head. This causes the air within to cool and condense. The loss of heat and the reduction of air causes an imbalance of pressure between the head and tummy. The air in the tummy expands and pushes down to adjust for the loss of air in the head. This forces some of the liquid up the tube into the head, which reduces the amount of air in the head even more. At the same time, the pressure in the tummy decreases. This causes evaporation of the liquid which creates more air and increases the pressure in the tummy thereby causing more liquid to be forced up the tube and into the head. The rising liquid raises the center of mass of the bird to the point where the head can no longer stay upright and so it tips forward into the glass. The level of liquid in the bulbs has been set so that when the bird drinks, the bottom of the tube is exposed. The angle of the dip allowed by the pivot has been calculated so that a bubble of air can rise through the tube and allow the liquid to drain back into the tummy, which causes the bird to go back upright. The water from the re-wet head begins to evaporate again and re-starts the motion. A bit complicated for younger children to understand, but still lots of fun to watch!
Bird Only Measures: 24.5cm (9 1/2 inches) tall
Bird with Stand Measures: 25.5cm (10 1/2 inches) tall
WARNING: This product is not a toy and is not intended for use by children under age 8. Use under adult supervision. Avoid breaking glass. Contains methelene chloride and may stain clothing and other surfaces. Do not swallow or allow to come into contact with eyes. Non-flammable. Keep away from flame and other heat sources.