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
Videos
Textbook Question
Chapter 5, Problem 5.55P
The heat flux in a reaction is estimated by Q = 5(T\ — FzJkJ/s. Two thermocouples are used to measure T\ and Ti. Each thermocouple hits a systematic uncertainty of 0.2 °C (95%). Based on a large sample of measurements, Ti = 180 °C, 7\ = 90°C, and the random standard uncertainty in each temperature measurement is 0.1 °C. Assume large degrees of freedom. Compare the uncertainty in heat flux if the thermocouple systematic errors are (a) uncorrelated and (b) correlated. Explain.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
The actual value of pressure differential for flow across a venturimeter is 60 mm WC. The measured values using a pressure sensor are; Confidence level 95% mm WC 59.8,59.2,59.7,60.2,60.3,60.1,60.5
Estimate
Bias uncertainty (1)
Precision uncertainty (2)
Total uncertainty (3)
n a certain dynamic measurement application the input(x) – output(y) relationship is given by
y=1+(1+x)e^(-x)
With what uncertainty must x be determined to yield a relative uncertainty of ±5 percent for y at a value of x = 2,4
Pressure distribution measurements are made on a two-dimensional wing model placed in a wind tunnel. The difference between the static pressure sockets on the surface and the static pressure of the free stream is measured. 30 data is taken at each measurement point. The average of the values measured from one of the sockets near the trailing edge was calculated as 2.30 Pa, and the standard deviation was calculated as 2.65 Pa. After applying the Chauvenet criterion to these measurement values, it was decided to eliminate 3 measurements and the new mean value was found to be 2.18 Pa and the standard deviation was 2.42. It was verified that the unexcluded data fit the normal distribution curve. Data above how many Pa and below how many Pa were eliminated? Estimate how many data have negative value (?<0) after elimination.
Chapter 5 Solutions
Theory and Design for Mechanical Measurements
Ch. 5 - Prob. 5.1PCh. 5 - Explain what is meant by the terms “true value,"...Ch. 5 - SJ An official Olympics timekeeper once stated,...Ch. 5 - A tachometer has an analog display dial graduated...Ch. 5 - An automobile speedometer is graduated in 5-mph...Ch. 5 - An engineer reads the height of a mercury...Ch. 5 - Prob. 5.8PCh. 5 - Two resistors arc to be combined to form an...Ch. 5 - An equipment catalog boasts that a pressure...Ch. 5 - The shear modulus, G, of an alloy can be...
Ch. 5 - Heat transfer from a rod of diameter D immersed in...Ch. 5 - Estimate the design-stage uncertainty in...Ch. 5 - Explain the critical dift'erence(s) between a...Ch. 5 - A displacement transducer has the following...Ch. 5 - Prob. 5.18PCh. 5 - For a thin-walled pressure vessel of diameter D...Ch. 5 - Suppose a measured normal stress contains three...Ch. 5 - Prob. 5.31PCh. 5 - The area of a flat, rectangular parcel of land is...Ch. 5 - Estimate the random standard uncertainty in the...Ch. 5 - Estimate the uncertainty at 95% confidence in the...Ch. 5 - One use for a GPS rangefinder is on the golf...Ch. 5 - A pressure measuring system outputs a voltage that...Ch. 5 - The density of a metal composite is to be...Ch. 5 - A temperature measurement system is calibrated...Ch. 5 - The power usage of a strip heater is to be...Ch. 5 - The power usage of a DC strip heater can be...Ch. 5 - A thermocouple is a temperature sensor made of two...Ch. 5 - Time variations in a signal require that the...Ch. 5 - A hand-held infrared thermometer from a well-...Ch. 5 - The pressure in a large vessel is to be maintained...Ch. 5 - The cooling of a thermometer (c.g., Exs. 3.3 and...Ch. 5 - A J-type thermocouple monitors the temperature of...Ch. 5 - The density of air must be known to within 0.5%....Ch. 5 - In pneumatic conveying, solid particles such as...Ch. 5 - A step test is run to determine the time constant...Ch. 5 - The acceleration of a cart down a plane inclined...Ch. 5 - The heat flux in a reaction is estimated by Q =...Ch. 5 - A comparative test uses the relationship R =...Ch. 5 - A sensitive material is to be contained within a...Ch. 5 - A geometric stress concentration factor, K,, is...Ch. 5 - In Problem 5.9, we assumed that the errors in die...
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
- A displacement transducer has the following specifications: Linearity error:±0.25% reading Drift:±0.05%/°C reading Sensitivity error: ±0.25% reading Excitation: 10-25 V Output: dc 0-5Vdc Range: 0-5 cm The transducer output is to be indicated on a voltme- ter having a stated accuracy of 0:1% reading with a resolution of 10 μV. The system is to be used at room temperature, which can vary by 10 °C. Estimate an uncertainty in a nominal displacement of 2 cm at the design stage. Assume 95% confidence.arrow_forwardAir flows at 20 oC through a 6 cm pipe. A square edged orifice plate with the diameter ratio β=0.4 , is chosen to meter the flow rate. A pressure drop of 250 cm H2O is measured at the flange taps with an upstream pressure of 93.7 kPa absolute. Take discharge coefficient ,C, as 0.60±1%. Assume that dimensions are known to within 0.025 mm, the systematic uncertainty in pressure is 0.25 cm H2O, and the pressure drop shows a standard deviation of 0.5 cm H2O in 20 readings. Upstream pressure is constant. In the flow measurement , determine the followings : a) The flow rate b) The systematic uncertainty c) The random uncertainty d) The total uncertaintyarrow_forwardCalculate the absolute uncertainty, fractional uncertainty, and percentile uncertaintyarrow_forward
- What is an example of experimental uncertainty?arrow_forwardTo measure the density of a stone, a digital scale and a beaker cup filled with water are used. The balance is used to measure the mass of the stone, while the beaker is used to measure the volume of the stone. It is known that the digital balance has a resolution of 0.1 g and that the beaker cup has a resolution of 5 ml. Repeated mass measurements return the following values: 250.0 g; 249.9 g; 250.3 g; 249.6g; 250.1 g; 249.7g; 250.4 g; 250.0 g; 248.8 g; 250.2 g The volume is measured only once. Placing the stone in the beaker, a volume of displaced water equal to 50 ml is measured. Using a k=2.5, check if the density of the stone is compatible or out of line with the value ρ = (4910 ± 65) kg.m-3 (a) none of the above (b) the values are compatible (c) missing data to perform the compatibility test (d) the values are discrepantarrow_forwardCardiologists use the short-range scaling exponent α1, which measures the randomness of heart rate patterns, as a tool to assess risk of heart attack. The article “Applying Fractal Analysis to Short Sets of Heart Rate Variability Data” compared values of α1 computed from long series of measurements (approximately 40,000 heartbeats) with those estimated from the first 300 beats to determine how well the long-term measurement (y) could be predicted the short-term one (x). Following are the data (obtained by digitizing a graph). Short Long 0.54 0.55 1.02 0.79 1.4 0.81 0.88 0.9 1.68 1.05 1.16 1.05 0.82 1.05 0.93 1.07 1.26 1.1 1.18 1.19 0.81 1.19 0.81 1.2 1.28 1.23 1.18 1.23 0.71 1.24 Note: This problem has a reduced data set for ease of performing the calculations required. This differs from the data set given for this problem in the text. Compute the least-squares line for predicting the long-term measurement from the short-term measurement.…arrow_forward
- 14. The diameter of a wire is measured using a micrometer. The uncertainty in the measurement is ±0.01 mm. The diameter D is 0.27 mm. What is the percent uncertainty in the AREA of the wire? A) 10 % B) 1 % cell C) 5. 7% D) 7.5arrow_forwardA load cell is calibrated in an environment at a temperature of 21°C and has the following deflcction/load characteristic: Load (kg) 0 50 100 150 200 Deflection (mm) 0.0 1.0 2.0 3.0 4.0 When used in an environment at 35°C, its characteristic changes to the following: Load (kg) 0 50 100 150 200 Deflection (mm) 0.2 1.3 2.4 3.5 4.6 Determine the sensitivity at 21°C and 35°C. Calculate the total zero drift and sensitivity drift at 35°C. Hence determine the zero drift and sensitivity drift coefficients (in units of pm/°C and (pm per kg)/(°C)).arrow_forwardA temperature measurement system is composed of a sensor and a readout device. The readout device has a claimed accuracy of 0.6 °C with a resolution of 0.1 °C. The sensor has an off-the-shelf limit of error of 0.5 °C. Estimate a design-stage uncertainty in the temperature indicated by this combination. A displacement transducer has the following specifications: Linearity error:±0.25% reading Drift:±0.05%/°C reading Sensitivity error: ±0.25% reading Excitation: 10-25 V Output: dc 0-5Vdc Range: 0-5 cm The transducer output is to be indicated on a voltme- ter having a stated accuracy of 0:1% reading with a resolution of 10 μV. The system is to be used at room temperature, which can vary by 10 °C. Estimate an uncertainty in a nominal displacement of 2 cm at the design stage. Assume 95% confidence.arrow_forward
- The transducer specified in Table 1.1 is chosen to measurea nominal pressure of 500 cm H2O. The ambient temperature is expected to vary between 18 ∘C and 25 ∘C duringtests. Estimate the possible range (magnitude) of each listedelemental error affecting the measured pressure refering to the solution provided online, Sensitivity error(eK) = (±0.0025)(500 cm H2O)= ± 0.75 cm H2O = ± 0.00375 V how do you get 0.75?? shoud it not be 1.25? according the answer, for sensitivityarrow_forwardA special sensor is designed to sense the percent vapor present in a liquid vapor mixture. If during a static calibration the sensor indicates 80 units when in contact with 100% liquid,0 units with 100% vapor ,and 40units with a 50:50% mixture,determine the static sensitivity of the sensorarrow_forwardThree engineers are independently estimating the spring constant of a spring, using the linear model specified by Hooke’s law. Engineer A measures the length of the spring under loads of 0, 1, 2, 4, and 6 lb, for a total of five measurements. Engineer B uses the same loads, but repeats the experiment twice, for a total of 10 independent measurements. Engineer C uses loads of 0, 2, 4, 8, and 12 lb, measuring once for each load. The engineers all use the same measurement apparatus and procedure. Each engineer computes a 95% confidence interval for the spring constant. If the width of the interval of engineer A is divided by the width of the interval of engineer B, the quotient will be approximately _____. Numeric Responsearrow_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 Press
Mechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSON
Thermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEY
Mechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage Learning
Engineering 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
What is Metrology in Mechanical Engineering? | Terminologies & Measurement; Author: GaugeHow;https://www.youtube.com/watch?v=_KhMhFRehy8;License: Standard YouTube License, CC-BY