Air Pressure By: The Furry Ewoks Orcutt Academy Ty Fredriks

Our Question: How does altitude affect air pressure?

Hypothesis We predict that air pressure was going to decrease with the altitude because the air is thinner at higher elevations. We researched on the internet about air pressure.

Materials Gondola Duct tape String Stop watch Hooks to attach the gondola to the balloon Lab pro (2) Barometer Balloon Hose reel Flag markers

Procedure We created our Gondola out of a cardboard box, duct tape, and string. We made sections for the lab pro and barometer before we came to balloon fest. We set up our lab pro and barometer on Logger Pro in the computer. Then we hooked it all up into our gondola. We attached two balloons to the gondola and took turns reeling it at a very steady pace out. Every 100 feet we attached a red flag to mark the distance the balloon has traveled.

Procedure Continued At 500 ft we stopped and let the barometer collect data for 1 minute, and then we measured at 1000 ft up waiting 2 minutes. On the way back down we waited 1 minute at 500 ft and 1 minute at 5 ft where we started from.

Discussion At 500 feet the pressure measurements were slightly different. This is probably because the wind affected the actual height of the balloon by moving the string. At 1000 feet, the graph of the data showed slight differences. We didn’t move the reel but the wind affected the height of 1000 ft Having two Barometers helped with getting the more accurate data and we could see that the trends were both the same. They both have a parabola form.

Raw Data Elevation (feet)Time interval (seconds) 5O-33 rising rising falling falling

Data Green line indicates rise in elevation found by converting kPa into meters ***Every 83 meters pressure drops by 1 kPa

First 30 seconds when gondola was at ground level Last minute when gondola returned to ground level Data shows the same pressure at ground level

When gondola reached 500 feet while rising When gondola reached 500 feet while falling Data shows similar pressures at 500 feet

Gondola at 1000 feet The lowest pressure shown on the graph corresponds to 1000 feet

Obstacles We attempted our experiment three times in order to get the correct data. Attempt #1: We only attached 1 balloon. We measured 3 minutes for every 100 feet. We were up in the air for 1 full hour. What we didn’t do was test the lab pro to see that it was working to it’s fullest potential, and it gave us odd results. The graph was bunched up and didn’t look accurate.

Obstacles Continued Attempt # 2: We got no data at all, because the laptop we were using was not syncing with the lab pro. We also added a second barometer to compare the results one inside the box and one outside the results had the same trend. Attempt # 3: We did a trial run to make sure that our lab pro worked correctly, after we collected all of our data we plugged it into the laptop and it wasn’t revealing any data. We tried a different computer and it was successful showing accurate data.

Conclusions We learned that air pressure is always changing, but as altitude increases air pressure decreases. Our hypothesis was correct, but there is always something influencing the air pressure readings such wind or weather. If we were ever to do this procedure again we would test all of our equipment before we launched.