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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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4Taping•Today’s lab we will use steel tapes tomeasure distances–Tapes are 100 feet long•Directly read to 1/100 of a foot•Has only foot marks except at the zero endTaping•Today’s lab we will use steel tapes tomeasure 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 endSystematic errors in taping•Length of tape•Change in temperature•Variation in pull on tape•Weight of the tape (sag)•AlignmentLength of Tape•This systematic error is resolved bycomparing the length of the tape to astandard–Standard are monuments with a knowndistance between them•Precisely measuredTemperature corrections•As it warms up Steel expands•As it gets colder Steel contracts•For our steel tapes we will use the followingformula–Ct= 0.00000645 x (T‐Ts) x L–Where•Ct= Correction to the measurement due to temperature•T = Temperature at the time of the measurement•Ts= Standardized Temperature•L = Length measured with the tape–Ctis added to the total length•It will be negative if T is less then TsPull corrections•In order to resolve errors associated with pullwe will do the following:–Pull when standardizing the tape at 10lbPull when using the tape for measurement at 10–lb•Pull will be determined using a tension scale attachedto the tape.