Theory and Design for Mechanical Measurements
6th Edition
ISBN: 9781118881279
Author: Richard S. Figliola, Donald E. Beasley
Publisher: WILEY
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 1, Problem 1.24P
A simple thermocouple circuit is formed using two wires of different alloy: One end of the wires is twisted together to form the measuring junction, and the other ends are connected to a digital voltmeter, forming the reference junction. A voltage is set up by the difference in temperature between the two junctions. For a given pair of alloy material and reference junction temperature, the temperature of the measuring junction is inferred from the measured voltage difference. What are the dependent and independent variables during practical use? What about during a calibration?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
QUESTION 2
Thermocouples are devices used to measure temperature of a given sample or the surrounding
medium. These devices feature a "bead", which has a spherical shape, and produces voltage upon change
in temperature. For an engineering application at a pharmaceutical company, thermocouple devices are
being tested for their responsiveness, i.e. how fast it can detect temperature changes in the environment
(surrounding air). The engineers at this company have specified design constraints for an ideal
thermocouple: it must detect temperature changes no later than 1.5 minute, and the reported
temperature value must be reasonably correct: at most %3 difference between measured and actual
temperature values is allowed.
Four thermocouples from different vendors are being tested. Relevant properties of these devices are
listed below:
Thermal conductivity Density
36 W/m*K
36 W/m*K
42 W/m*K
33 W/m*K
Specific Heat
140 kJ/kg*K
120 kJ/kg*K
150 kJ/kg*K
160 kJ/kg*K
Device
Bead Diameter…
Using the colored bands on the two resistors at your table, you determine that the two resistances of the resistors are 200 ohms with 5%
tolerance and 100 ohms with a 20% tolerance. What would you expect the equivalent resistance of the two resistors to be (including the
uncertainty) if they are connected in series?
) ohms
±
Check
Truncation errors are increased as the round-off errors are decreased.Group of answer choices True False
Say, you have a thermometer and you are checking the temperature of a body that has a temperature of 36o Using your thermometer five times, it gives you the following measurements: 29oC, 29.2oC, 29.3oC, 28.9oC, and 29.1oC. What can we conclude about the accuracy and the precision of the thermometer?Group of answer choices The thermometer is not accurate and not precise The thermometer is faulty. The thermometer is accurate and precise The thermometer is not accurate but precise.
Say, you have a thermometer and you are checking the temperature of a body that has a temperature of 36o Using your thermometer five times, it gives you the following measurements: 36oC, 35.6oC, 36oC, 37oC, and 36.2oC. What can we conclude about the accuracy and the precision of the thermometer?Group of answer choices The thermometer is accurate and precise. The thermometer is accurate but not precise. The…
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
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- Question 5.1: A thermopile is constructed with chromel-alumel materials. Five junctions are maintained at 400-C and five junctions are maintained at 100°C. The output of the thermopile is connected to a potentiometer. Answer the following questions: a) Draw the equivalent circuit and indicate all the given information. b) What is the voltage induced by the potentiometer? Given: Table 8.30 Temperature. °C -150 -100 <-50 <<-25 0 25 50 75 100 150 200 300 400 500 600 800 1000 1200 1500 1750 Thermal emf in absolute millivolts for commonly used thermocouple combinations, according to ITS(90) (Reference junction of 0 C)¹ Copper vs. Constantan (7) -4.648 -3.379 -1.819 -0.940 0 0.992 2.036 3.132 4.279 6.704 9.288 14.862 20.872 Chromel vs. Constantan (E) -7.279 -5.237 -2,787 -1.432 0 1.495 3.048 4.657 6.319 9.789 13.421 21.036 28.946 37.005 45.093 61,017 76.373 Iron vs. Constantan ( -6.500 -4.633 -2.431 -1.239 ( 1.277 2.585 3.918 5.269 8.010 10.779 16.327 21.848 27.393 33.102 45.494 57.953…arrow_forwardA chamber of unknown volume is filled with an unknown amount of ideal gas. A cylinder with an open bottom and calibrated volume is connected to the chamber and is closed with a movable piston. A gas pressure sensor is also mounted on the chamber as shown in the figure. The whole experimental setup is kept at a constant temperature of 300 K. Doris moves the piston from mark 0 to mark 200 mL in steps of 50 mL and records the corresponding pressure in the chamber (see the table below). She moves the piston very slowly and waits several minutes before recording the pressure values. VCyl(mL) P(105N/m2)) 0 4.35 50 3.85 100 3.50 150 3.15 200 2.90 Determine the volume of the chamber using Doris's data in the table. (Note: This is a problem that requires linearization of data.) Determine the number of moles of gas. (Note: This is a problem that requires linearization of data.)arrow_forwardA J-type thermocouple is used to measure the unknown steady-state temperature of a liquid. The sensor outputs a voltage of 2.532 mV. Using Equation 2 and Table 1.2, determine the unknown temperature. Show all calculations and assume the thermocouple is referenced to 0 °C. T = a₁ + a₂V + · ...+ a₂V² a a₁ 0.000 000 1.978 425 x 10-² -2.001 204 x 10¹7 1.036 969 x 10-¹1 -2.549 687 x 10-16 3.585 153 x 10-21 -5.344 285 x 10.26 5.099 890 x 10:³1 Table 1.2 -J-type thermocouple polynomial coefficients over the range of 0°C to 760°C ± 0.04°C 8₂ a3 a4 (2) as as a7arrow_forward
- 2:45 ull 4G A moodle1.du.edu.om 1- A J-Type thermocouple referenced to 80°F has a measured output emf of 2.878 mV. What is the temperature of the measuring junction? 2- Assume that the measured temperature is 250° F, what should be the output voltage if the reference temperature is 90 °F. RK: if the temperature values are not in the table, you have to use interpolation. Response to question 2: The measured output voltage (mV) Select one: O a. 2.764 b. 4.769 c. 5.762 O d. 3.768arrow_forwardThe objective of this question is to give the missing information about the reading of thermocouple type J. The temperatures are in degrees Celsius. The temperature is 100 degrees and the reference is 50. The reading voltage is (mV) Choose... The temperature is 95 and the reference is zero, so the voltage is (mV) Choose... The reference is 30 and the reading voltage is 8.687 mV, The temperature is Choose... + The temperature is 256 degrees and the reference is 75 degrees. The reading voltage is (mV) Choose... +arrow_forwardA new electronic component for aircraft is tested to withstand temperatures as low as -50°F. One engineer suggests that the device cannot actually stand temperatures that low. What are the Type I and Type II errors? Type I: The device CAN NOT withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN.Type II: The device CAN withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN NOT. Type I: The device CAN withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN NOT.Type II: The device CAN NOT withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN. Is the answer the first or second bullet point?arrow_forward
- 4. For a particular thermocouple, if one junction is maintained at 0°C (cold junction) and the other junction is used as a probe to measure the desired Celsius temperature t, the voltage V generated in the circuit related to the temperature t as V = t (a + bt) Further, for this thermocouple, when V is in millivolts, the two constants are a = 0.25 and b = -5.5 x10+. Determine the value of V if the measured temperature is 100°C.arrow_forwardRecord the dimensions of the known (calibration) block using the caliper and dial gauge on the table below. Indicate the units of each measurement. Calculate the average length of each side of the block. Dimension Caliper (Units) 0.995 1.455 0.985 Ruler(in) A: 0.9 B: 1.5 C: 0.9 A B C Dimension A B Instrument Use the average dimensions (see Problem 2a) of the known block to calibrate the LVDT at your workstation. Record the voltage on the table below: LVDT Offset: 0.556 (Do not include the offset value in your average dimensions) C Ave Dimension (Units) (Dial Gauge) 0.997 1.659 0.949 0.964 in 1.538 in 0.945 in oltage Average Dimension 1.244 volt 1.994 1.28 0.964 in 1.538 in 0.945 inarrow_forwardThe following resistance of a platinum resistance thermometer were measured at a range of temperature. Determine the measurement sensitivity of the instrument in milli Ohms/ oC. Resistance (mῼ) Tempreture (oC) 210k 110 217k 89 221k 68 228k 47arrow_forward
- A thermocouple was used to measure the temperature. Over the range of temperatures expected in the experiment, a linear regression analysis was performed for the temperature as a function of voltage. The best-fit equation was T = (-0.008563 + 220*V), where V is the thermocouple voltage. The voltage was fed into a 11-bit A/D converter with a voltage range of -8 V to 8 V. Determine the measurement resolution (in °C) due to the ADC? O 0.851 None O 3.113 1.710 0.393 4.960 1.144 O 3.797arrow_forwardA resistor is measured with a device which has a known precision of ±0.075 k2 when a large number of measurements is taken. How many measurements are necessary to ensure that the resistance is within ±0.05 k2 with a 0.1l percent level of significance? Use the t -distribution.arrow_forwardNewton's Law of cooling states that the rate at which heat is lost by a heated body is proportional to the difference in temperature between the body and the surrounding medium. Match the following statements/phrases with the corresponding item in the drop down box. Choices in the box 1. In accordance with the stated law obove, we have the equation? 2. If a thermometer is taken outdoors where the temperoture is 5 deg C, from a room in which the temperature is 20 deg C and the reading drops 10 deg C in one minute, the working equation is? 3. In the obove problem, separoting the variables and integrating will result to? 4. In the obove problem, how long, in minutes, after its removal from the room will the reading be 6 deg C? 5. In the obove problem, ofter 30 seconds, whot will be the thermometer reading? 5.2 dT(body temp)/dt = k(Temp of medium - 5) dr(body temp)/dt = k(Temp of body - Temp of medium) Temp of body = Cenkt +5 2.5 13.7 dr(body temp)/dt = k(Temp of medium - Temp of body)…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY
Elements Of Electromagnetics
Mechanical Engineering
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:9780134319650
Author:Russell C. Hibbeler
Publisher:PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:9781259822674
Author:Yunus A. Cengel Dr., Michael A. Boles
Publisher:McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:9781118170519
Author:Norman S. Nise
Publisher:WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:9781337093347
Author:Barry J. Goodno, James M. Gere
Publisher:Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:9781118807330
Author:James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:WILEY
Understanding Conduction and the Heat Equation; Author: The Efficient Engineer;https://www.youtube.com/watch?v=6jQsLAqrZGQ;License: Standard youtube license