Suppose you are a teaching assistant for the penny experiment, and your job is t
ID: 714999 • Letter: S
Question
Suppose you are a teaching assistant for the penny experiment, and your job is to review the student’s data for possible problems. What would you expect to see in a student’s data set for the following problems? What course of action would you suggest to the student?
a. A student misreads the balance and puts the decimal point in the wrong place for all 20 measurements.
b. One student weighs all 20 pennies without checking to make sure the balance reads zero between each weighing.
c. One student misunderstands the instructions and weighs one penny twenty times.
d. A student doesn’t want to wait for an analytical balance, so he finds a balance that weighs to 0.01 grams and uses that balance to weigh the pennies.
Errors in Measurements Version 8/29/2018
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e. A student gets one penny that was minted early in 1982 when some pennies were still made with 95% copper
Explanation / Answer
a) The measures taken can present a certain precision, since they are all under the same error, but they will not be completely accurate. The solution would be to verify the weight of some of the tabulated coins and confirm which would be the correct decimal, then correct the rest.
b) By not calibrating the analytical balance for each weigh, some agent (humidity, air, grease) may interfere with the actual weight of the coin, increasing the weight progressively with each weighing. The course of actions to take, it would be irremediably, to carry out the experiment again, taking into account the calibration between each weighing.
c) This student will surely have very precise and exact values, but nothing real, since he would only have a single sample. Repeat experiment with the 20 coins.
d) It will have results with little appreciation for the weight of the coins, possibly, most of the coins weigh similarly. It is recommended to use analytical balance.
e) This currency would be different, therefore it will have a value that is far from the set of values. It is advisable to change this currency for one to the same conditions.