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the drunken engineer

Two systems were set up and analyzed: the first, to use simple pendulums to calculate the value of acceleration due to gravity; and the second, to analyze movement of physical pendulums to measure moment of inertia. Length of the pendulums and their masses were varied; these values and the resulting periods were recorded. By plotting values on an x-y graph, the experimental value of g was found to be 9.76 m/s2, a 0.48% difference from the accepted value of 9.80 m/s2. Two different physical pendulums and their respective motions were considered. Using measured values for mass, period, and center of rotation, an experimental value for each object was found. For the disk-shaped object, the average of experimental I values was 2.45x10-3 kg-m, a 2.08% difference from the theoretical value of 2.50x10-3 kg-m. In the case of the ring-shaped object, the average of experimental I values was 8.26x10-4 kg-m, a 0.15% difference from the theoretical value of 8.25x10-4 kg-m. In conclusion, this laboratory was a success, and the equations for moment of inertia, and the value of g were proven true. The discrepancy in the final results compared to theoretical values can be attributed to losses of angular momentum through friction, air resistance and others, as well as inaccurate equipment and human error.