Phy 122
Your 'bottle thermometer' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** Your optional message or comment: **
I got really kinda confused with the bottom part of the analysis if you could help me with that.
** What happens when you pull water up into the vertical tube then remove the tube from your mouth? **
Water will be held in the tube after it has been pulled up the collumn as long as the end it capped by the mouth or by another piece of tubing.
When the capping of the tube is removed the water flows back down the collumn thus not attaining the same initial height of water in the column. This happens because pressure keeps the water up in the tube.
** What happens when you remove the pressure-release cap? **
Yes air will escape from the system. The water in the collumn before removing the cap was above the level of water in the bottom but when removing the cap the water dropped down below the level of the water in the bottle. The pressure of the liquid overcomes the pressure of the air resulting in the lowering of the water in the collumn.
** What happened when you blew a little air into the bottle? **
After bubbles are blown into the system. This creates a vacuum that quickly pulls the water up the tube when you release this tube from your mouth. When uncapping the pressure-valve tube the water in the vertical tube decreases slightly. I did not expect the water to shoot out of the tube and make a mess.
** Your estimate of the pressure difference due to a 1% change in pressure, the corresponding change in water column height, and the required change in air temperature: **
101,000 N/m^2
.1 cm
1.0%
100 * .01 = 1 kpa
100 + 1 = 101 kpa 101 kpa * 1000 pa = 101000 N/m^2
101,000/100,000 = 1.01
10 cm * .01 = .1 cm
1.01 * 300 K = 303 K (303 K - 300 K / 303 K ) * 100% = 1.0%
** Your estimate of degrees of temperature change, amount of pressure change and change in vertical position of water column for 1% temperature change: **
3
1,000 N/m^2
.1 cm
100 * .01 = 1 kpa
Your units are incorrect here. To get the 1000 N/m^2 change (which is correct) would require that rho g * `dy = 1000 N/m^2, so that `dy = 1000 N/m^2 / (rho g) = 1000 N/m^2 / (1000 kg/m^3 * 9.8 m/s^2) = .1 meter, approx., not .1 cm.
100 + 1 = 101 kpa 101 kpa * 1000 pa = 101000 N/m^2
101,000/100,000 = 1.01
10 cm * .01 = .1 cm
1.01 * 300 K = 303 K (303 K - 300 K / 303 K ) * 100% = 1.0%
** The temperature change corresponding to a 1 cm difference in water column height, and to a 1 mm change: **
30 K
3 K
3 K = .1 cm or 1 mm, so there are 10 mm in 1 cm so 10 mm * 3 K = 30 K
Good reasoning, but see my preceding note related to units. .1 cm would be only 1/100 of the vertical change which corresponds to a temperature change of 3 K.
** water column position (cm) vs. thermometer temperature (Celsius) **
23.0 C, 10.8 cm
23.5 C, 10.9 cm
23.5 C, 11.0 cm
24.0 C, 11.6 cm
24.0 C, 11.6 cm
23.9 C, 12.0 cm
23.9 C, 12.6 cm
23.9 C, 12.8 cm
23.9 C, 12.8 cm
23.9 C, 12.9 cm
23.9 C, 13.0 cm
23.9 C, 13.2 cm
23.0 C, 13.5 cm
23.2 C, 13.8 cm
23.2 C, 14.0 cm
23.5 C, 14.1 cm
23.0 C, 14.2 cm
23.2 C, 14.3 cm
23.5 C, 14.8 cm
23.0 C, 14.8 cm
** Trend of temperatures; estimates of maximum deviation of temperature based on both air column and alcohol thermometer. **
Even though the temperature fluctuated it was still consistent with normal room temperature; however, the height of the water in the collumn was continually and gradually on the rise. The height of the water changed by 4 mm per minute.
** Water column heights after pouring warm water over the bottle: **
24.0 C, 12.2 cm
30.0 C, 29.0 cm
31.0 C, 23.0 cm
31.0 C, 20.5 cm
31.0 C, 18.5 cm
31.0 C, 17.0 cm
31.0 C, 16.5 cm
31.0 C, 16.0 cm
26.0 C, 15.5 cm
26.0 C, 14.5 cm
25.0 C, 14.5 cm
25.0 C, 14.5 cm
24.0 C, 14.7 cm
23.5 C, 14.2 cm
23.0 C, 14.0 cm
** Response of the system to indirect thermal energy from your hands: **
Yes, the water rose from 14.0 cm to 18.0 cm.
** position of meniscus in horizontal tube vs. alcohol thermometer temperature at 30-second intervals **
23.0 C, 16.5 cm
23.0 C, 16.5 cm
23.0 C, 16.5 cm
23.5 C, 16.8 cm
23.0 C, 17.0 cm
23.2 C, 17.2 cm
23.5 C, 17.4 cm
23.6 C, 17.5 cm
23.6 C, 17.5 cm
24.0 C, 17.7 cm
** What happened to the position of the meniscus in the horizontal tube when you held your warm hands near the container? **
The water in the tube rose up to 20.5 cm while the temperature was constant at 24 degrees C. The height of the water went down to 19 cm within the minute.
** Pressure change due to movement of water in horizonal tube, volume change due to 10 cm change in water position, percent change in air volume, change in temperature, difference if air started at 600 K: **
** Why weren't we concerned with changes in gas volume with the vertical tube? **
The system was a closed system, therefore the volume would have been somewhere and would not have made a significant difference in the estimates of the temperature change.
** Pressure change to raise water 6 cm, necessary temperature change in vicinity of 300 K, temperature change required to increase 3 L volume by .7 cm^3: **
** The effect of a 1 degree temperature increase on the water column in a vertical tube, in a horizontal tube, and the slope required to halve the preceding result: **
** Optional additional comments and/or questions: **
4 hours
** **
Your work is quite good. You may at least one error in units, so be sure to see my note.