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course Phy 242
May 10
Brief Bottle Experiment 3c
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Repeat experiment 3 b, with one modification: Instead of squeezing the bottle to raise water, you will heat it up, using hot tap water.
Heat the system gradually, by first turning on the water so that is just trickles down one side of the container. Adjust the flow so that the water in the vertical tube rises just above the bottlecap. Take measurements to determine the vertical position in the tube, and the change in the length of the air column in the pressure tube compared to its original length.
Increase the flow of hot water so that the level in the vertical tube increases by another 10 cm or so, and repeat your measurements.
Repeat this process for two more steps.
Report your data in the usual manner, with at least a brief explanation, and include a table of the heights to which water was raised vs. the length of the air column as a percent of its original length. Add a third column which gives the pressure resulting from each squeeze, as indicated by the height of the water in the vertical tube (that pressure should be given in Pascals).
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When I trickled the hot tap water, hitting the side, I saw no change in water level.
When I increased the flow of hot water a quarter throttle, and measured 10cm, it took 45 seconds to raise it.
When I increased the flow of hot water a half throttle, and measured 10cm, it took 15 seconds to raise it.
When I increased the flow of hot water a full throttle, and measured 10cm, it took not even 5 seconds to raise it.
With the increase in temperature and volume of water flowing on it, caused the system to increase at a more rapid rate.
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Now set the vertical tube to allow water to run out so that it could be collected at the vertical level of your last measurement, and turn the tap on full. You won't need to measure the collected water, but watch the pressure tube as the water flows out and report what you observe.
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I don’t think I did this right but when I heated it up, it took a while, but water did flow out of the pressure tube, not at a fast rate though.
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Sketch a pressure vs. volume graph for the process you observed (that is, the pressure of the gas in the bottle vs. the volume of the gas in the bottle). You may use reasonable estimates for the volumes.
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When I graphed the pressure vs. volume graph, it looked like an e^(-x) graph. Isn’t this Boyle’s Law?
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Self-critique (if necessary):
&#Good work on this lab exercise. Let me know if you have questions. &#