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course Phy 242
April 19 around 9pm.
Brief Bottle Experiment 3A________________________________________
This experiment requires the bottlecap with two bottlecaps and multiple tubes, two bottles (bottles designed for carbonated drinks are stronger than and therefore preferable to bottles designed for water, juice, tea, etc., bit either will do), a sink with hot and cold running water, a cup or shallow container, a ruler, and a teaspoon.
The tube common to both bottlecaps will be called the 'vertical tube', even if it isn't used in the vertical position.
The other two tubes coming from each bottlecap are the 'pressure tube' (the longer of the two) and the 'exhaust tube' (the shorter of the two), also sometimes referred to as the 'pressure-release tube'.
The word 'cap' will refer to the removable caps that can be used to seal the ends of the tubes.
Siphon a 'water plug' into each pressure tube and cap it, forming in each a sealed air column at least 20 cm long. This air column will be used to measure pressure changes. Measure the length of each air column.
Fill one bottle with water, and fill the other about 3/4 full. All the tubes except the vertical tube should be capped. The vertical tube should remain uncapped at both ends, and once the system is set up both ends should remain in water throughout.
Elevate one bottle and siphon water from that bottle into the other until both bottles are about equally full. The water level should be above the cylindrical portion of the bottle (within the rounded portion of the bottle near the top, above the cylindrical portion of the container). From the end of the siphoning process until completion of this exercise, both ends of the vertical tube should remain beneath the water level in their respective bottles, and the vertical tube should remain full of water.
Bring the bottles to the same vertical level and tighten both bottlecaps. Mark the 'water end' of the air column in each tube, or alternatively, carefully measure the lengths of the air columns in the two pressure tubes. Also mark or carefully measure the water level in both bottles.
Now raise one bottle about 30 cm higher than the other and take the measurements necessary to find the change in the water level in each bottle, and the change in the length of each air column.
Report your measurements and the change in each measurement below, along with an explanation of your results. Include a table indicating the percent change in the length of each air column, the percent change in water depth for each bottle, and your estimate of the change in air volume in each.
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The water levels in the two bottles are 16cm and 18cm. I tried to get them as close as possible, but I have two completely different bottles, so I’m sure they’re close. The air columns are 20cm each. After raising one bottle 30cm higher than the other, NOTHING happened. This is so because the entire system is capped/sealed and therefore resulting in no change, no matter how high it’s raised.
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Uncap the exhaust tube in the upper container and repeat your measurements. Report your new information below, including tables indicating the respect percent changes in the various measured quantities.
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After uncapping the shorter tube in the upper container, I saw a slight change in the air column of the lower bottle. After a minute, it starting raising water into the air column, but not much, maybe 1 cm change.
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Lower the upper bottle to the level of the first. Take measurements to again determine the various changes. Report your new information below, including tables indicating the respect percent changes in the various measured quantities.
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When the two bottles are at the same levels, NOTHING happens, once again. Same measurements as the first time.
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What do you think is going on here? Try to explain as much as you can about what you have observed:
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Nothing moves if the system is sealed. If it’s uncapped then the air allows the water to move. When one is elevated, it allows the water to move from one bottle to the other.
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&#This looks good. Let me know if you have any questions. &#