The micrometer screw gage can be checked against precision gage blocks for accuracy (perhaps the instrument was abused?). The instrument must be applied with a certain feel to obtain accurate and repeatable readings. The special graduations have a limited accuracy and it is necessary to estimate any reading more refined than the graduations. If the instrument can measure from zero to say one inch, a fixed error would be a larger percent of 0.1 inch than of 1.0 inch. Instrument errors (pressure gages, etc.) are often specified as % f.s. (percent full scale). Taking the average reading of say ten readings (and throwing out any obvious flyers) should provide a more accurate reading than a single reading.How to calculate percentage uncertainty of the reading from micrometer screw guage?
Take multiple readings of the same standard piece multiple times with and compute the mean and standard deviation. Divide the standard deviation by the standard length and multiply by 100 to get the percentage of repeatability error for that micrometer. Also compute the difference between the mean and the standard to see how accurate the micrometer is. The total uncertainty is the square root of the sum of the squares of the accuracy, the repeatability and the error of the standard.How to calculate percentage uncertainty of the reading from micrometer screw guage?
gigigigiiggi ........................................鈥?gooHow to calculate percentage uncertainty of the reading from micrometer screw guage?
use your fingers to count numerical data
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