1.The thickness of a gage block is measured five times using an instrument that has a resolution of 0.001 cm. The following measurements are obtained (in cm): 1.100, 1.110, 1.090, 1.095, and 1.105. The true gauge block thickness is known to be 1.050 cm. Use this information to answer the following questions: a. What errors or sources of measurement error can be identified in the example? (Hint: there are three). Identify each one as a random or systematic uncertainty. b. Estimate the magnitudes of each of these uncertainties. Wherever possible, estimate random uncertainties at a 95% probability/confidence level. c. Based on the uncertainties determined in part b, estimate the overall uncertainty of a measurement obtained by this instrument.
Theory and Design for Mechanical Measurements
Measurement is a term that refers to analyzing a manufactured component regarding the degree of accuracy for dimensions, tolerances, geometric profile, roundness, flatness, smoothness, etc. Measurement always involves comparing the manufactured component or the prototype with a standard specimen whose dimensions and other parameters are assumed to be perfect and do not undergo changes with respect to time.Precisely in mechanical engineering the branch that deals with the application of scientific principles for measurements is known as metrology. The domain of metrology in general deals with various measurements like mechanical, chemical, thermodynamic, physical, and biological measurements. In mechanical engineering, the measurements are limited to mechanical specific such as length, mass, surface profile, flatness, roundness, viscosity, heat transfer, etc.
Basic principles of engineering metrology
Metrology is described as the science of measurement, precision, and accuracy. In other words, it is a method of measurement based on units and predefined standards.
1.The thickness of a gage block is measured five times using an instrument that has a resolution of 0.001 cm. The following measurements are obtained (in cm): 1.100, 1.110, 1.090, 1.095, and 1.105. The true gauge block thickness is known to be 1.050 cm. Use this information to answer the following questions:
a. What errors or sources of measurement error can be identified in the example? (Hint: there are three). Identify each one as a random or systematic uncertainty.
b. Estimate the magnitudes of each of these uncertainties. Wherever possible, estimate random uncertainties at a 95% probability/confidence level.
c. Based on the uncertainties determined in part b, estimate the overall uncertainty of a measurement obtained by this instrument.
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 2 images
