Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073401331
Author: William Navidi Prof.
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 3, Problem 12SE
The article “Effect of Varying Solids Concentration and Organic Loading on the Performance of Temperature Phased Anaerobic Digestion Process” (S. Vandenburgh and T. Ellis, Water Environment Research, 2002:142–148) discusses experiments to determine the effect of the solids concentration on the performance of treatment methods for wastewater sludge. In the first experiment, the concentration of solids (in g/L) was 43.94 ± 1.18. In the second experiment, which was independent of the first, the concentration was 48.66 ± 1.76. Estimate the difference in the concentration between the two experiments, and find the uncertainty in the estimate.
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The article “Effect of Varying Solids Concentration and Organic Loading on the Performance of Temperature Phased Anaerobic Digestion Process” (S. Vandenburgh and T. Ellis, Water Environment Research, 2002:142–148) discusses experiments to determine the effect of the solids concentration on the performance of treatment methods for wastewater sludge. In the first experiment, the concentration of solids (in g/L) was 43.94 ± 1.18. In the second experiment, which was independent of the first, the concentration was 48.66 ± 1.76. Estimate the difference in the concentration between the two experiments, and find the uncertainty in the estimate.
The depth of wetting of a soil is the depth to which water content will increase owing to
extemal factors. The article "Discussion of Method for Evaluation of Depth of Wetting in
Residential Areas" (J. Nelson, K. Chao, and D. Overton, Journal of Geotechnical and
Geoenvironmental Engineering, 2011:293-296) discusses the relationship between depth of
wetting beneath a structure and the age of the structure. The article presents measurements
of depth of wetting, in meters, and the ages, in years, of 21 houses, as shown in the
following table.
Age
Depth
7.6
4
4.6
6.1
9.1
3
4.3
7.3
5.2
10.4
15.5
5.8
10.7
4
5.5
6.1
10.7
10.4
4.6
7.0
6.1
14
16.8
10
9.1
8.8
Compute the least-squares line for predicting depth of wetting (y) from age (x).
b. Identify a point with an unusually large x-value. Compute the least-squares line that
results from deletion of this point.
Identify another point which can be classified as an outlier. Compute the least-squares
line that results from deletion of the outlier,…
The article "Experimental Measurement of Radiative Heat Transfer in Gas-Solid
Suspension Flow System" (G. Han, K. Tuzla, and J. Chen, AIChe Journal, 2002:1910-
1916) discusses the calibration of a radiometer. Several measurements were made on the
electromotive force readings of the radiometer (in volts) and the radiation flux (in kilowatts
per square meter). The results (read from a graph) are presented in the following table.
Heat flux (y)
15 31 51 55 67 89
Signal output (x) 1.08 2.42 4.17 4.46 5.17 6.92
Compute the least-squares line for predicting heat flux from the signal output.
If the radiometer reads 3.00 V, predict the heat flux.
If the radiometer reads 8.00 V, should the heat flux be predicted? If so, predict it. If
not, explain why.
C.
Chapter 3 Solutions
Statistics for Engineers and Scientists
Ch. 3.1 - The boiling point of water is measured four times....Ch. 3.1 - Two thermometers are calibrated by measuring the...Ch. 3.1 - The weight of an object is given as 67.2 0.3 g....Ch. 3.1 - Prob. 4ECh. 3.1 - A person stands on a bathroom scale. The reading...Ch. 3.1 - A person gets on and off a bathroom scale four...Ch. 3.1 - In a hypothetical scenario, the National Institute...Ch. 3.1 - Prob. 8ECh. 3.1 - A new and unknown weight is weighed on the same...Ch. 3.1 - Prob. 10E
Ch. 3.1 - The length of a rod was measured eight times. The...Ch. 3.2 - Assume that X and Y are independent measurements...Ch. 3.2 - The length of a rod is to be measured by a process...Ch. 3.2 - The volume of a cone is given by V = r2h/3, where...Ch. 3.2 - In the article The Worlds Longest Continued Series...Ch. 3.2 - A cylindrical hole is bored through a steel block,...Ch. 3.2 - A force of F = 2.2 0.1 N is applied to a block...Ch. 3.2 - The period T of a simple pendulum is given by...Ch. 3.2 - The specific gravity of a substance is given by G...Ch. 3.2 - Prob. 10ECh. 3.2 - According to Newtons law of cooling, the...Ch. 3.2 - Prob. 12ECh. 3.2 - Nine independent measurements are made of the...Ch. 3.2 - A certain scale has an uncertainty of 3 g and a...Ch. 3.2 - The volume of a rock is measured by placing the...Ch. 3.2 - A student measures the spring constant k of a...Ch. 3.2 - A certain chemical process is run 10 times at a...Ch. 3.2 - An object is weighed four times, and the results,...Ch. 3.2 - Prob. 19ECh. 3.2 - Prob. 20ECh. 3.3 - Find the uncertainty in Y, given that X = 2.0 0.3...Ch. 3.3 - Given that X and Y are related by the given...Ch. 3.3 - The volume of a cone is given by V = r2h/3, where...Ch. 3.3 - Prob. 4ECh. 3.3 - The period T of a simple pendulum is given by...Ch. 3.3 - The change in temperature of an iron bar brought...Ch. 3.3 - The friction velocity F of water flowing through a...Ch. 3.3 - The refractive index n of a piece of glass is...Ch. 3.3 - The density of a rock will be measured by placing...Ch. 3.3 - The conversion of ammonium cyanide to urea is a...Ch. 3.3 - Prob. 11ECh. 3.3 - Prob. 12ECh. 3.3 - The acceleration g due to gravity is estimated by...Ch. 3.3 - Refer to Exercise 4. Assume that T = 298.4 0.2 K....Ch. 3.3 - Refer to Exercise 5. a. Assume g = 9.80 m/s2...Ch. 3.3 - Refer to Exercise 6. Assume that c = 448 J/kgC and...Ch. 3.3 - Prob. 17ECh. 3.3 - Refer to Exercise 8. Assume the critical angle is...Ch. 3.3 - Refer to Exercise 9. Assume that the mass of the...Ch. 3.3 - Prob. 20ECh. 3.4 - Find the uncertainty in U, assuming that X = 10.0 ...Ch. 3.4 - The volume of a cone is given by V = r2h/3, where...Ch. 3.4 - From a fixed point on the ground, the distance to...Ch. 3.4 - Refer to Exercise 10 in Section 3.2. Assume that ...Ch. 3.4 - When air enters a compressor at pressure P1 and...Ch. 3.4 - One way to measure the water content of a soil is...Ch. 3.4 - Prob. 7ECh. 3.4 - Prob. 8ECh. 3.4 - The Beer-Lambert law relates the absorbance A of a...Ch. 3.4 - In the article Temperature-Dependent Optical...Ch. 3.4 - Refer to Exercise 12 in Section 3.2. Assume that 0...Ch. 3.4 - Prob. 12ECh. 3.4 - Archaeologists studying meat storage methods...Ch. 3.4 - Prob. 14ECh. 3.4 - A cylindrical wire of radius R elongates when...Ch. 3.4 - Prob. 16ECh. 3.4 - Refer to Exercise 16. In an experiment to...Ch. 3.4 - The vertical displacement v of a cracked slurry...Ch. 3.4 - The shape of a bacterium can be approximated by a...Ch. 3.4 - Prob. 20ECh. 3.4 - Refer to Exercise 10 in Section 3.2. Assume that ...Ch. 3.4 - Refer to Exercise 5. Assume that P1 = 15.3 0.2...Ch. 3.4 - Refer to Exercise 7. Assume that p = 4.3 0.1 cm...Ch. 3.4 - Prob. 24ECh. 3.4 - Refer to Exercise 12. Estimate n, and find the...Ch. 3.4 - Refer to Exercise 14. Assume that l = 10.0 cm ...Ch. 3.4 - Prob. 27ECh. 3.4 - Refer to Exercise 16. Assume that T0 = 73.1 0.1F,...Ch. 3.4 - Prob. 29ECh. 3.4 - Prob. 30ECh. 3.4 - Prob. 31ECh. 3 - Prob. 1SECh. 3 - Prob. 2SECh. 3 - Prob. 3SECh. 3 - Prob. 4SECh. 3 - Prob. 5SECh. 3 - Let A and B represent two variants (alleles) of...Ch. 3 - The heating capacity of a calorimeter is known to...Ch. 3 - Sixteen independent measurements were made of the...Ch. 3 - If two gases have molar masses M1 and M2, Grahams...Ch. 3 - A piece of plywood is composed of five layers. The...Ch. 3 - The article Effect of Varying Solids Concentration...Ch. 3 - Prob. 13SECh. 3 - Prob. 14SECh. 3 - Prob. 15SECh. 3 - The mean yield from process A is estimated to be...Ch. 3 - The flow rate of water through a cylindrical pipe...Ch. 3 - Prob. 18SECh. 3 - The decomposition of nitrogen dioxide (NO2) into...Ch. 3 - Prob. 20SECh. 3 - A track has the shape of a square capped on two...Ch. 3 - Prob. 22SECh. 3 - Prob. 23SE
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