Michael Gugliotta 10/17/14 Chemistry Period 8 Title: Comparing Units of Distance Research Question: How do SI units and English units compare? Introduction: SI units and English units are a very important part of measuring around the world. English units, which are inches, is the most common unit of measure in America. SI units, which are centimeters, are most commonly used in Europe. These units can help us measure many things such as the length of a book or a piece of wood. In this lab, we had to determine the length of 10 lines in inches and in centimeters. We did this so we can find the slope of our measurements and to find the percent error. Percent error is a statistic that is used to determine how far an observed value deviates from the true value. The formula for percent error is the absolute value of the observed value (the value you get when conducting the experiment) minus the accepted value (which is the value that we already know) over the accepted value multiplied by 100. This lab also gives us a better understanding on how to measure using SI and English units and why they are important. …show more content…
Materials: The materials of this experiment are: • English ruler • Metric ruler Methods: The methods of this experiment are: 1.
First, we had to measure each of the lines (Lines A-J) in inches and centimeters. 2. Then, we had to create a graph on a separate sheet of paper and make the measurements of inches in the x-axis and centimeters in the y-axis. We did this to determine our slope. 3. Lastly, we had to draw a line through the points and determine the slope. Results: Line Inches Centimeters A 6.20
15.8 B 2.25 5.5 C 4.06 10.3 D 1.69 4.2 E 6.88 17.5 F 2.88 7.4 G 5.13 13.1 H 0.94 2.4 I 3.81 9.7 J 4.75 12.1 Slope is 2.5619 rounded to 2.56 Discussion: In the data above, it shows us many things. Its shows that the slope of each centimeter to inch is 2.56. This shows that my hypothesis is supportive because we are comparing the centimeters to inches by using percent error. 2.56 is being used as our observed value. 2.54 is our accepted value for centimeters to inches. It also shows that our measurements are not always accurate. A way to make our results more accurate, is by repeating the experiment multiple times. By doing this method, we can also improve our experiment. The more accurate our results are, the more accurate the slope of centimeters to inches will be. Questions and Conclusions: 1. Based on your graph, how many centimeters are in 6 inches? 15.7 centimeters 2. Based on your graph, how many inches are in 10. cm? 3.8 inches 3. What does the slope of this graph tell about the relationship between centimeters and inches? The slope of this graph tells us that for each inch, you will have 2.56 cm. 4. The accepted value of centimeters per inch is 2.54 cm/in. What is your percentage error?(Do your calculations below) Accepted Value: 2.54 cm/in Observed Value: 2.56 cm/in Absolute Error: 0.8 cm/in Percentage error: 80% 5. What are some sources of error? Some sources of error are: • The ruler • The experiment was only performed once Relevant Vocabulary: • Percent error • Accepted value • Observed value • Absolute value • Slope • Inches • Centimeters • Metric system Literature cited: None
...e been beneficial to the experiment. An error may have occurred due to the fact that measurements were taken by different individuals, so the calculations could have been inconsistent.
Possible sources of error in this experiment include the inaccuracy of measurements, as correct measurements are vital for the experiment.
... measure. They will not want the hassle of remembering two different measurements throughout their lives. Americans are not very stubborn and are willing enough to change to a simpler system of measurements.
When the eggs are dropped onto the pillow, the eggs will bounce a little and stay whole.
This shows that there is a difference of 2cm between A and B, and B
Discussion: The percent of errors is 59.62%. Several errors could have happened during the experiment. Weak techniques may occur.
two lines of different lengths, while the lines are the same size. This illustrates the fact
The task of this lab is to create and analyze hypotheses of the different relationships between the properties of gasses. These properties include temperature, pressure and volume. The ideal gas law is the source for many of these hypotheses and are tested through the various known laws of gasses. Such laws include Lusaacs Law, Charles Law and Boyles Law. The data, gathered from the results of the experiments mentioned above, was then graphed to show the relationship between the properties that gasses inhibit. The data provided was also utilized to derive a proportionality constant, k. Pressure rises when temperature rises, pressure rises when volume falls and volume rises when temperature rises. All of these outcomes were observed during the
The purpose of the projectile lab is to test the validity of the law of conservation of energy. The application of this law to our everyday lives is a surprisingly complicated process. Conservation of energy states that energy cannot be created or destroyed, but that it can be transferred from one form to another. Consider the projectile lab from document A that this essay is based upon. In an ideal experiment, the projectile is isolated from everything except the gravitational field. In this case, the only force acting on the particle is gravity and there are only two forms of energy that are of interest: the energy of the particle due to its motion (defined as kinetic
from 10cm to 50cm to make it easier to see the difference in a graph.
end of the ruler to read of the measurements. After I had put on all
I predict that the as I increase the height of the slope (or the angle
If I were using a cut out of length 1cm, the equation for this would
I have also included in this diagram the labels c, x and y, these show
In the past, people have always tried their own ways of using daily measurements. It was needed and used for daily trade as well as further businesses. These things could only have been made if the people knew they were being fair and honest; hence, the reason that different measurements needed to exist. Many short distance measurements were based on the lengths of the human body. The width of a thumb was used to resemble the inch, which we used today in the English System of Measurements. The foot, which is twelve inches, was compared to the length of the human foot; however, today it is derived to be longer than most people’s feet. The yard, which is equal to three feet, was inferred to be the length from the tip of the nose, to the end of the middle finger when the arm and hand are extended. The Anglo Saxons of England measured these short differences in their own ways too. The length of three barleycorns was their length of the inch (it was very close to the modern length). Then in 1066, the Normans conquered England and brought back to England the Roman tradition of the twelve inch foot. During the reign of Henry I the foot became official and was engraved on the base of a column of St. Peter’s church in London (Rowlett, R. (2001). A dictionary of units of measurement. English customary weights and measures). He also arranged the yard to be established in England as well. Although, inches, feet, yards etc. measured shorter distances, miles were used to measure much longer distances. This mile was a Roman unit, which was primarily the length of 1,000 paces of a Roman legion. The “pace” was meant to be two steps, about five feet, which measured the mile to be roughly about 5,000 feet.