Theory and Design for Mechanical Measurements
6th Edition
ISBN: 9781118881279
Author: Richard S. Figliola, Donald E. Beasley
Publisher: WILEY
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Textbook Question
Chapter 1, Problem 1.38P
Explain the potential differences in the following evaluations of an instrument’s accuracy. Figure 1.11 will be useful, and you may refer to ASTM El77 if needed.
- The closeness of agreement between the true value and the average of a large set of measurements.
- The closeness of agreement between the true value and an individual measurement.
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Check out a sample textbook solutionStudents have asked these similar questions
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.
Q. Based on the calibration curves, find out the respective sensitivities of the
displacement measurement.
1.
Strain (UE)
Strain (UE)
0.01
0.00
-0.01
-0.02
-0.03
-0.04
0.0
0.01
0.00
-0.01
-0.02
0
-0.03
-0.0003-0.0009
-0.04
Strain vs. Displacement (Pushing)
-0.0369*x + -3.1E-03 R² = 0.984
0.0
0:0063
-0.011
0.1 0.2 0.3
-0.0152
-0.0049
0.1 0.2
-0.0088
-0.0195
0.3
Strain vs. Displacement (Releasing)
-0.0378*x + 2.16E-03 R² = 0.991
-0.0231
-0.0265
-0.0124
-0.0163-
0.4 0.5 0.6 0.7 0.8 0.9 1.0
Displacement (in)
-0.02
-0.0298
0.4 0.5 0.6
Displacement (in)
-0.0325
-0.0235
0.7
-0.0272
-0.0352
0.8
-0.0379
-0.0318
-0.0379
0.9 1.0
Describe errors which might occur during the use of the external standards calibration method and lead to erroneous results and determine whether these errors are systematic, random or personal errors.
Atleast 6 errors.
Chapter 1 Solutions
Theory and Design for Mechanical Measurements
Ch. 1 - Prob. 1.1PCh. 1 - Prob. 1.2PCh. 1 - Prob. 1.3PCh. 1 - Prob. 1.4PCh. 1 - Prob. 1.5PCh. 1 - Discuss how the resolution of the display scale of...Ch. 1 - Prob. 1.7PCh. 1 - Prob. 1.8PCh. 1 - Prob. 1.9PCh. 1 - Prob. 1.10P
Ch. 1 - State the purpose of using randomization methods...Ch. 1 - Provide an example of repetition and replication...Ch. 1 - Develop a test plan that might be used to estimate...Ch. 1 - Develop a test plan that might be used to evaluate...Ch. 1 - A race engine shop has just completed two engines...Ch. 1 - A thermodynamics model assumes that a particular...Ch. 1 - Regarding the Mars Climate Orbiter spacecraft...Ch. 1 - A large batch of carefully made machine shafts can...Ch. 1 - Suggest an approach or approaches to estimate the...Ch. 1 - Suggest a test matrix to evaluate the wear...Ch. 1 - Figure 1.15 Orifice flow meter setup used for...Ch. 1 - The sale of motor fuel is an essential business in...Ch. 1 - Using either the ASME 19.5 or ISO 5167 test...Ch. 1 - A simple thermocouple circuit is formed using two...Ch. 1 - 1.25 A linear variable displacement transducer...Ch. 1 - For the LVDT calibration of the previous problem,...Ch. 1 - A manufacturer wants to quantify the expected...Ch. 1 - Prob. 1.28PCh. 1 - As described in a preceding problem, the...Ch. 1 - Light gates may be used to measure the speed of...Ch. 1 - You estimate your car’s fuel use by recording...Ch. 1 - When discussing concomitant methods, we used the...Ch. 1 - Prob. 1.33PCh. 1 - For the strain gauge calibration of the previous...Ch. 1 - The acceleration of a cart down a plane inclined...Ch. 1 - In general, what is meant by the term “standard”?...Ch. 1 - A common scenario: An engineer has two pencil-...Ch. 1 - Explain the potential differences in the following...Ch. 1 - Research the following test standards and codes....Ch. 1 - A hotel chain based in the United States contracts...Ch. 1 - Test code ASTM 558-13 allows for the comparison of...Ch. 1 - Suggest a reasonable number of significant digits...Ch. 1 - Using spreadsheet software (such as Microsoft...Ch. 1 - Prob. 1.44PCh. 1 - Round the following numbers to 3 significant...Ch. 1 - Express the result, rounding to an appropriate num...Ch. 1 - Express the result by rounding to an appropriate...Ch. 1 - A car’s speed is determined by the time it takes...Ch. 1 - How much error could you tolerate in (1) book...Ch. 1 - Apply the guidelines to determine the number of...Ch. 1 - Using a tape measure having 1 mm graduations, the...Ch. 1 - Show how the following functions can be...Ch. 1 - Prob. 1.53PCh. 1 - For the calibration data of Table 1.5, determine...Ch. 1 - Prob. 1.55PCh. 1 - Each of the following equations can be represented...Ch. 1 - Plot y = 10e“° 5x volts on in semilog format (use...Ch. 1 - Prob. 1.58PCh. 1 - Prob. 1.59P
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