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 8, Problem 8.21P
A temperature difference of 3.0 °C is measured using a thermopile having three pairs of measuring junctions, arranged as shown in Figure 8.23.
a. Determine the output of the thermopile for J-type thermocouple wire, if all pairs of junctions sense the 3.0 °C temperature difference. The average temperature of the junctions is 80 °C.
b. If the thermopile is constructed of wire that has a maximum emf variation from the NIST standard values of ±0.8% (95%), and the voltage measuring capabilities in the system are such that the uncertainty is ±0.0005 V (95%), perform an uncertainty analysis to estimate the uncertainty in the measured temperature difference at the design stage.
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When the cold junction of a thermocouple thermometer is at 0° C and the hot junction at 100°C the millivoltmeter shows a deflection of 4.2 mV towards the left. The cold junction is now put in an unknown temperature while maintaining the hot junction at 100°C. The millivoltmeter now shows a deflection of 5.2 mV towards the right. Calculate the unknown temperature
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Chapter 8 Solutions
Theory and Design for Mechanical Measurements
Ch. 8 - Prob. 8.1PCh. 8 - Fixed temperature points in the International...Ch. 8 - Answers to the following questions may be found in...Ch. 8 - Calculate the resistance of a platinum wire that...Ch. 8 - Plot the resistance of a platinum wire that is 5 m...Ch. 8 - An RTD forms one arm of a Wheatstone bridge, as...Ch. 8 - An RTD forms one arm (/?4) of a Wheatstone bridge,...Ch. 8 - Research and describe current state-of-the-art...Ch. 8 - Prob. 8.9PCh. 8 - 8.10 Estimate the required level of uncertainty in...
Ch. 8 - 8.11 A thermistor is placed in a 100 °C...Ch. 8 - Prob. 8.12PCh. 8 - Prob. 8.13PCh. 8 - The thermocouple circuit in Figure 8.45 represents...Ch. 8 - The thermocouple circuit in Figure 8.45 represents...Ch. 8 - The thermocouple circuit in Figure 8.45 is...Ch. 8 - 8.17 a. The thermocouple shown in Figure 8.46a...Ch. 8 - Prob. 8.18PCh. 8 - Prob. 8.19PCh. 8 - A temperature measurement requires an uncertainty...Ch. 8 - A temperature difference of 3.0 °C is measured...Ch. 8 - Complete the following table for a J-type...Ch. 8 - Complete the following table for a T-type...Ch. 8 - Prob. 8.24PCh. 8 - 8.25 You are employed as a heating, ventilating,...Ch. 8 - A J-type thermocouple for use at temperatures...Ch. 8 - A J-type thermocouple is calibrated against an RTD...Ch. 8 - A beaded thermocouple is placed in a duct in a...Ch. 8 - Consider a welded thermocouple bead that...Ch. 8 - Prob. 8.30PCh. 8 - Prob. 8.31PCh. 8 - Consider the typical construction of a sheathed...Ch. 8 - An iron-constantan thermocouple is placed in a...Ch. 8 - Figure 8.48 Schematic diagram for Problems 8.33,...Ch. 8 - Figure 8.48 Schematic diagram for Problems 8.33,...Ch. 8 - 8.36 In Example 8.5, an uncertainty value for Rf...Ch. 8 - The thermocouple circuit shown in Figure 8.49...Ch. 8 - Prob. 8.38PCh. 8 - 8.39 A thin-film heat flux sensor employs a K-type...Ch. 8 - A thin-film heat flux sensor has a sensitivity uV...Ch. 8 - 8.41 A T-type thermopile is used to measure...Ch. 8 - 8.42 A T-type thermocouple referenced to 0 °C is...Ch. 8 - A T-type thermocouple referenced to 0 °C develops...Ch. 8 - 8.44 A temperature measurement system consists of...
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