external image AEmWuTT.jpgAs spring is right around the corner, it's almost time to start with some property maintenance. I have a fence in my backyard that needs painting. For my experiment I would like to compare temperature and time. I will be collecting data on how long it takes paint to dry at various temperatures from 30 degrees up to about 73 degrees. To conduct this experiment I will paint one picket of the fence at each different temperature. For example, on one day when it is say 30 degrees out, I will paint one picket and see how long that takes to dry. I will do this for 9 other temperatures and record my data. From previous knowledge I know that the cooler the temperature the longer it takes for paint to dry, so I predict that it will take more time to dry in cooler temperatures than in hotter temperatures.

Temperature (F)
Time (hour/min)
30
7 hours 10 min.
35
6 hours 44 min.
42
6 hours 5 min.
47
5 hours 35 min.
52
5 hours 2 min
57
4 hours 32 min.
60
4 hours 3 min.
63
3 hours 36 min
67
3 hours 5 min.
73
2 hours 47 min.

Correlation Coefficient: r= -.9949
Coefficient of Determination: R^2= .9899 or 98.99%
Least Squares Regression Equation: y=-.1089x + 10.4479

Analysis:
As soon as I was finished graphing my data on the calculator I could tell I had done it correctly because the graph showed a negative linear correlation. I knew this was correct because as I stated in my mini-proposal, I knew as the temperature increased the drying time decreased. My hypothesis of predicting that the cooler the temperature the longer it will take to dry was proven correct. My data graphed perfectly and there was a rather strong, negative, linear relationship between the data. There was almost a perfect negative linear relationship between the 2 sets of data and you can tell this by looking at the correlation coefficient, which is very close to -1.
As far as the confounding influences go, there are many that could affect the data and conclusion of this experiment. One confounding influence could be the fact that I did not factor in the wind chill and how fast the wind was blowing when I was doing this experiment. The wind chill could have had a major impact on this data because it could have made the temperature a lot cooler, which would have also made the dry time longer. Another confounding influence could be that my dad helped me paint some of the pickets and we may have had different techniques to painting that could also affect the drying time. He could have painted a thick layer, while I painted a thicker layer, which would also influence the time it took for them to dry. A thick layer and a thin layer could be painted in the same temperature, but a thicker layer is still going to take longer to dry.
My data may not be 100% correct, but despite these minor influences my data still supports my hypothesis and the fact that it does take paint longer to dry the colder the temperature.