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How did the drinking bird from the 1960s work to continue to bob its head into a glass of water?
D4est
The classic bobbing or drinking bird toy has amused kids and adults for years. It appears to be perpetual motion (impossible) but is actually a heat engine with a lot of thermodynamics going on. Although the bird is often thought to be a recent invention it was invented in 1945 and patented in 1946. The "toy" was the brainchild of to PHD candidates, Miles V. Sullivan and George H. Shackley. The science is so complex that it has been the basis of several thermodynamics courses.
The classic bird is made from two glass bulbs joined by a glass tube. The tube extends almost to the bottom of the bottom bulb. It is joined to the top bulb but only at the end. The bulb contains some fluid which evaporates and condenses easily at about room temperature. The bird so far is similar in construction to the "love meters" which move fluids from one bulb to the other based on the heat of your hand.
The other parts of the bird are a bird beak or head made of absorbent material, a pivot which lets the bird balance on a stand, and a glass of water for the bird to dip its beak into. The actual operation of the bird is the result of several gas laws, evaporative cooling and, pressure changed due to heat, leverage and showmanship!
What happens is:
- The birds felt (or similar) head is dampened with water and positioned in front of a glass of water located so that the beak will swing down into the water if it moves forward about the pivot.
- The water on the felt evaporates cooling the head, creating a vacuum in the gases (through condensation of the gas there) and subsequently sucking up fluid from the bottom bulb
- This makes the head heavier and it swings down dipping the nose into the water.
- The water absorbs into the beak fabric, warming the fabric and the bulb, which in turn warms the gases in the head.
- The warmed gases expand increasing the top bulb pressure and expelling the fluid back into the bottom bulb
- The head (now lighter as the fluid is gone) raises, the water starts to evaporate cooling the head and restarting the cycle
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What is the amount of liquid a drinking glass hold?
One drinking glass holds about 230 ml ( milliliters )
An old remedy for a pair of nested drinking glasses that stick together is to run water at different temperatures into the inner glass and over the surface of the outer glass which water will be hot?
put the cold water into inner glass and hot water out the glass
Which water should be cold and cold when doing a old remedy for a pair of nested drinking glasses?
Put cold water inside the glasses. Dip the outer glass into hot water. The outer glass expands, the inner glass contracts.
What is on the side of your drinking glass on a hot day?
Water, condensed from the air, onto the glass. The rate of condensation depends on the relative humidity and the temperature differential between the glass and the air.
If glass bottle filled with water is placed in the freezer it breaks after some time because?
Assuming the container is filled to the top with minimal airspace, the water will freeze becoming ice. It will continue to get colder and start expanding until it fills the glass bottle and then force the glass to break as it continues to expand.
What is the shape of water in a drinking glass?
It is the shape of the glass.
What glass goblets are for?
Drinking wine and water
Why should you not pour very hot water into a drinking glass?
because the glass will pop if you put the very hot water into the glass
Can you have a glass of water?
Depending on the accessibility of both clean drinking water and a glass to pour it in, you might or might not be able to have it.
Does water burn calories while your drinking it?
Drinking water does burn calories and drinking an 8-ounce glass of cold water burns 9.25 calories more than drinking room temperature water.
What kinds of muscles are used in drinking glass of water?
Hey
What unit would you use to measure the height of a drinking glass?
Glass of water
Which is the best unit for measuring the amount of water in a drinking glass?
The best unit of measure to use when measuring the amount of water in a drinking glass is ounces. A liquid measuring cup can be used to measure the ounces of water.
What is the amount of liquid a drinking glass hold?
One drinking glass holds about 230 ml ( milliliters )
The water in your drinking glass may have once been part of?
The water in your drinking glass may have once been part of one of the Great Lakes. These Great Lakes are in the United States of America.
How many fluid oz in a water glass?
There are 8 ounces in an average drinking glass.
An old remedy for a pair of nested drinking glasses that stick together is to run water at different temperatures into the inner glass and over the surface of the outer glass which water will be hot?
put the cold water into inner glass and hot water out the glass
