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# They are resolved by averaging measurements

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They are resolved by averaging measurements Systematic Errors These are errors that can be determined They are resolved by applying corrections

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4 Taping Today’s lab we will use steel tapes to measure distances Tapes are 100 feet long Directly read to 1/100 of a foot Has only foot marks except at the zero end Taping Today’s lab we will use steel tapes to measure distances Tapes are 100 feet long Directly read to 1/100 of a foot Has only foot marks except at the zero end Has ticks every 0.01 of a foot at zero end Systematic errors in taping Length of tape Change in temperature Variation in pull on tape Weight of the tape (sag) Alignment Length of Tape This systematic error is resolved by comparing the length of the tape to a standard Standard are monuments with a known distance between them Precisely measured Temperature corrections As it warms up Steel expands As it gets colder Steel contracts For our steel tapes we will use the following formula C t = 0.00000645 x (T T s ) x L Where C t = Correction to the measurement due to temperature T = Temperature at the time of the measurement T s = Standardized Temperature L = Length measured with the tape C t is added to the total length It will be negative if T is less then T s Pull corrections In order to resolve errors associated with pull we will do the following: Pull when standardizing the tape at 10lb Pull when using the tape for measurement at 10 lb Pull will be determined using a tension scale attached to the tape.