Image taken from Prof. Mason's Day 2 Class Notes
We used the above set-up in order to determine the linear coefficient of thermal expansion of the rod. Based on our findings we needed to determine what the rod was made of.
Our calculations from the above experiment were as follows:
After determining the linear coefficient of thermal expansion we propagated uncertainty for the experiment and found the uncertainty to be as follows:
After we included our uncertainty we found our answer for the linear coefficient of thermal expansion of the rod to be:
We compared our calculated answer to a table of values for the coefficient of thermal expansion for several materials at 20°C. After comparing the values, we narrowed the possibilities down to Aluminum, α=2.4×10^-5 (1/°C), and Lead, α=2.9×10^-5 (1/°C). However, with reasoning we determined that the rod most likely would have been made of of Aluminum rather than Lead.
Latent Heat of Fusion/Vaporization of Ice/Water
In several different science courses, even in our own physics book, they depict the Temperature vs Time graph for Water to be as follows:
[Figure 17.21 from University Physics w/Modern Physics 13th Edition]
After testing this in class we class we saw that the actual Temp vs Time graph for Ice and Water was very different from what most physics and chemistry books depicted. Rather than being straight transitions the actual graph had smoother transitions.
After determining the above relationship we set out and experimented to find the latent heat of vaporization for water. In order to to this we placed 200 mL of water inside a styrofoam cup and took the system's (cup+water) initial mass at room temperature, 206.8 g. We then placed the cup in a mug to help stabilize it and submerged an immersion heater (Power=304±1.6 W) in the water along with a temperature probe.
We mixed the water in order to have equal distribution of heat and waited until it came to a boil. We recorded the data and logger pro and found the below results.
We remeasured the cup and water and found the mass to now have been 187.8 g. Using initial and final temperature, along with the total time allowed to boil, we calculated the latent heat of vaporization for water to be 1.712×10^6 J.
We took this value and compared it to the class average.
In excel we calculate the standard deviation of all of the classes values for Latent Heat of Vaporization. Taking this into account our experimental value for Latent Heat of Vaporization falls within the range of possibilities. Considering that the true Latent Heat of Vaporization for water is 2.256×10^6 J/kg it is clear that there was a huge error in our experiment. This can be largely attributed to the measuring of mass. In the heating process some mass was lost when the water began boiling and some spilled out. Even more mass was lost through out the experiment due to some mass evaporating even before the water reached its boiling point. Also, if the mass was not recorded at the exact time we stopped the experiment than additional mass was lost through evaporation in the time taken to weigh the cup and water.
Ideal Gas Law
Boyle's Law: Pressure vs. Volume
Image taken from Prof. Mason's Day 2 Class Notes
In order to determine the relationship between pressure and volume we observed what happened when 35cc of air was compressed by 5cc and noted the change in pressure. As the volume was decreased the pressure of the system increased. However, the relationship was not proportional, as depicted in the below graph of Pressure vs. Volume.
The fit line that best fit these points was an inverse graph. This makes sense because pressure and volume are inversely proportional when temperature is kept at a constant, which was the case for this mini experiment. The slope for this graph was 3288 which represents...
Charles' Law II: Pressure vs. Temperature
Image taken from Prof. Mason's Day 2 Class Notes
For this experiment we wanted to determine the relationship between pressure and volume. To see this correlation we used a 150mL Erlenmeyer Flask filled with air and attached it to a force sensor. We then proceeded to place the flask in an ice cold cup and and in a cup of warm water, we then recorded the temperature and pressure at those times. This time the relationship between pressure and temperature turned out to be proportional as seen below.
The fit line that best fit this graph was clearly linear, thus proving that the relationship was proportional when volume was held constant. The slope for the Pressure vs. Temperature turned out to be 0.2368 kPa/°C. This slope likely represents...
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