Uncertainity In The Scientific Process

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Theory When preforming an experiment using the scientific process one of the most essential components is comparing theory to actual measurements. This relies on the accuracy and uncertainty of the measurement itself. If an actual measurement proves the theory wrong it you must know the uncertainty so you can try to figure out where the error took place. Uncertainty can arise from a few different areas; they are statistical variation, measurement precision, or systematic error. Systematic error is in most cases human error like not measuring the experiment with proper tools or failing to account for external factors before performing the experiment. On the other hand statistical variation and measurement uncertainty cannot be avoided in …show more content…
Next we calculated the normalized results and found out that the coins we used were fair. They had and average of .47 per penny and a sigma of .14. These values include .50 in there range so they could be determined as fair. The percent uncertainty was then calculated and it came out to be 29.78 percent. The analysis of the 144 pennies started by determining an expected value of sigma, which is 6. So that means that is half of the pennies are supposed to land on heads than the value that we were supposed to obtain was anywhere between 66 and 78. When doing this experiment my partner and I came up with head 67 times so this does agree with the theory. The average number of heads per penny was .47, and when using the expected sigma of 6 the sigma per penny was .04 and the percent uncertainty per penny was 8.60. Both values were less than the values that were obtained for the 16 pennies. In the second part of the experiment we measured the length, width, and height of a black of wood with a ruler using centimeters. The dimensions were 30.2cm by 8.4cm by 3.7cm and the uncertainty of the ruler was .1 cm. the weight of the block came out to be 534.8 grams with and uncertainty of .1 …show more content…
Those values were 3.6 for area, 25.3 for volume, and 10.8 for density. After that the percent uncertainty was calculated by using the formula 100(uncertainty)/(original value). The values for area, volume, and density are 1.53, 4.23, and 4.09. The expected percentage was then calculated by adding up the percentages from the dimensions used in calculating the quantity. For area the expected was 1.52, the volume 4.23, and for density 4.29. Finally I found the expected uncertainty buy using the formula (original value)*(expected percentage uncertainty)/100. The values for area, volume, and density were 3.86, 39.7, and 24.36. Comparing all of these values it shows that they are very similar and are in and expected range of each other. Based on my results I believe that the type of wood that my block is elm. I choose this because when looking a the table in section 4 it says that the density on elm is 570 kg/m^3 and my calculated density was 569.77

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