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Jayman_PE

ERRATA - Goswami's Practice Exams (New)

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I purchased this text about 1 month ago with high hopes. I am not impressed. After going over both AM exams and the Construction PM exam, I am either

1. An idiot who is taking too long to complete most of these problems.

or

2. The text was poorly written by someone (or people) who did not read the NCEES syllabus and have no concept of what an average 6 minute problem looks like.

So the worry is I may have wasted the equaivalent of 2 to 3 days and money on this text. In short most problems take too long, some are unrelated to the exam (i.e. traffic studies for the AM?), others require obscure equations (i.e. you would probably need the Green Book, etc..., and I'm not a transpo person, to solve.)

There are some good problems in here for sure, but too many take too long. They sort of remind me of the 6 - minute solutions texts and the CERM Practice Problems by Lindeburg. The main difference being those problems are written clearly overall. Anyway, here is what I found so far.

ERRATA

Page 195, Problem 36. Should be 243% increase. (not 143%). Unless I'm mistaken.

Page 37, Problem 120. A lousy question - finding the general relationship for critical velocity/depth for a triangular section. I would like to see if most Civil Hydraulic Professors can solve this inside of 6 minutes? I post this as an Errata because it should be left out of the question set. Maybe a good question for the PM exam, but not AM. Again, 6 minutes.

Page 212, Problem 123. I get V = 6.18 ft/sec. I think Goswami's answer (7.15) works too. Might be a bad coincidence of two intersecting solutions.

Page 40, Problem 126. Did the Author take time to read the NCEES Breadth syllabus for Transportation? Nowhere do I see traffic counts, studies, of any kind. Therefore, this should be removed from the AM and placed in the Transpo PM problem set.

Page 42, Problem 132. See previous statement. Wasted ink.

Page 46, Problem 140. Poorly written. Not clear what we are asked to find: net cost of what? Crashing Schedule option vs. Normal Schedulle?

Again, I have only gone through the AM (#1 and #2) and Construction PM Exams so those venturing further will no doubt uncover more frustration.

thanks,

Jason

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I bought Goswami's practice exams before his book was published so I received 2 AM exams and 1 PM (Transpo) via e-mailed PDF. Here is what I sent him for the AM Exam #1. (I didn't have enough time to get to the AM exam #2 nor the PM exam before taking/passing the exam in April '11)

In the question 102 diagram, the elevation text overlaps with the tank diagrams

In question 103, remove the "-" before 1.7 inches

In question 112, remove the open parenthesis before A, B, C and D

In the question 123 diagram, change 4 tons to 24 tons

In the question 129 answers A and B, add commas to 2,600 and 3,500

In question 130, add "minimum" after "ladders" in the question

In question 137, indicate the units for the answer choices (inches)

In question 137, correct the spelling of patters to patterns

In solution 101, change 12 <dot> 69 to 12.69. In solution 103, change 1 <dot> 7 to 1.7 and 185 <dot> 5 to 185.5. In solution 106, change 117 <dot> 4 to 117.4. Etc., etc (There are many other instances on other pages too)

In solution 104, change the exponent "<delta>/3" to "8/3". Also, shouldn't the solution specify if n=nf or if n does not = nf for the d/D?

In solution 106, change the first gamma to gamma <sub> d

In solution 107, it appears that c = 1200. What is c and how is it calculated?

In solution 114, what AASHTO Table is being referred to? (Exh 3-2, pg 115 AASHTO does not include 5%)

In solution 118, a quicker method to calc BODu might be to use BODu ~=1.463 x BOD5

In solution 119, change C<sub>z to C<sub>c.

In solution 122, add a comma after "lb" and before "V", first line

Edited by ptatohed

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I purchased this text about 1 month ago with high hopes. I am not impressed. After going over both AM exams and the Construction PM exam, I am either

1. An idiot who is taking too long to complete most of these problems.

or

2. The text was poorly written by someone (or people) who did not read the NCEES syllabus and have no concept of what an average 6 minute problem looks like.

So the worry is I may have wasted the equaivalent of 2 to 3 days and money on this text. In short most problems take too long, some are unrelated to the exam (i.e. traffic studies for the AM?), others require obscure equations (i.e. you would probably need the Green Book, etc..., and I'm not a transpo person, to solve.)

There are some good problems in here for sure, but too many take too long. They sort of remind me of the 6 - minute solutions texts and the CERM Practice Problems by Lindeburg. The main difference being those problems are written clearly overall. Anyway, here is what I found so far.

ERRATA

Page 195, Problem 36. Should be 243% increase. (not 143%). Unless I'm mistaken.

Page 37, Problem 120. A lousy question - finding the general relationship for critical velocity/depth for a triangular section. I would like to see if most Civil Hydraulic Professors can solve this inside of 6 minutes? I post this as an Errata because it should be left out of the question set. Maybe a good question for the PM exam, but not AM. Again, 6 minutes.

Page 212, Problem 123. I get V = 6.18 ft/sec. I think Goswami's answer (7.15) works too. Might be a bad coincidence of two intersecting solutions.

Page 40, Problem 126. Did the Author take time to read the NCEES Breadth syllabus for Transportation? Nowhere do I see traffic counts, studies, of any kind. Therefore, this should be removed from the AM and placed in the Transpo PM problem set.

Page 42, Problem 132. See previous statement. Wasted ink.

Page 46, Problem 140. Poorly written. Not clear what we are asked to find: net cost of what? Crashing Schedule option vs. Normal Schedulle?

Again, I have only gone through the AM (#1 and #2) and Construction PM Exams so those venturing further will no doubt uncover more frustration.

thanks,

Jason

I've only done 3/4 of the questions of the AM #1 and found a few errors along the way, I'm waiting to hear back from Professor but I have to agree that some of these questions seem way more complicated than I would expect. Also it's not clear on some of his solutions where he's getting some of his values.

I know the CERM questions are harder than the actual exam questions, but any feedback about this exam book versus the actual questions? I'm confident in structural (my discipline) but after donig some of these water/environment questions in the morning #1, i feel like a dope. :beat:

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Page 37, Problem 120. A lousy question - finding the general relationship for critical velocity/depth for a triangular section. I would like to see if most Civil Hydraulic Professors can solve this inside of 6 minutes? I post this as an Errata because it should be left out of the question set. Maybe a good question for the PM exam, but not AM. Again, 6 minutes.

The equation to solve this is given on page 513 of his book. I don't know if you own his book or not so this may not help.

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I think he asks for VDS on 122 but solves for VSS in the solution. I emailed him to see if I'm correct or if I'm looking at this wrong.

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I think he asks for VDS on 122 but solves for VSS in the solution. I emailed him to see if I'm correct or if I'm looking at this wrong.

I emailed him and, once again, I am an idiot! :)

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Page 37, Problem 120. A lousy question - finding the general relationship for critical velocity/depth for a triangular section. I would like to see if most Civil Hydraulic Professors can solve this inside of 6 minutes? I post this as an Errata because it should be left out of the question set. Maybe a good question for the PM exam, but not AM. Again, 6 minutes.

The equation to solve this is given on page 513 of his book. I don't know if you own his book or not so this may not help.

Benny,

My point is the problem is way over 6 minutes. His problems are based upon the structure of his book, not the structure of the NCEES syllabus. Assume you do not have his book (I do) and you encounter that problem on the exam. What to do? Can't look it up in CERM, it's not there. So you need to derive it. And fast. Not a 6 minute problem, more like a 10-15 minute, unless your a Water Resources pro (I'm not).

Having said that I do like his book. It's a perfect companion to the CERM. If I can't find something in the CERM, or just need clarity, I reach for Goswami's text. It's very good. I just don't care for his sample exams overall. Again, there are very good questions in there, it's just that most take way beyond 6 minutes.

thanks,

Jason

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Page 37, Problem 120. A lousy question - finding the general relationship for critical velocity/depth for a triangular section. I would like to see if most Civil Hydraulic Professors can solve this inside of 6 minutes? I post this as an Errata because it should be left out of the question set. Maybe a good question for the PM exam, but not AM. Again, 6 minutes.

The equation to solve this is given on page 513 of his book. I don't know if you own his book or not so this may not help.

Benny,

My point is the problem is way over 6 minutes. His problems are based upon the structure of his book, not the structure of the NCEES syllabus. Assume you do not have his book (I do) and you encounter that problem on the exam. What to do? Can't look it up in CERM, it's not there. So you need to derive it. And fast. Not a 6 minute problem, more like a 10-15 minute, unless your a Water Resources pro (I'm not).

Having said that I do like his book. It's a perfect companion to the CERM. If I can't find something in the CERM, or just need clarity, I reach for Goswami's text. It's very good. I just don't care for his sample exams overall. Again, there are very good questions in there, it's just that most take way beyond 6 minutes.

thanks,

Jason

I don't have the Goswami practice problem book because I bought his practice exams from him when they used to be e-mailed PDFs but I think you guys are talking about this problem, right? Practice exam No. 2, #120. A triangular channel with 1V:3H sides, Q=10 CFS, S = 0.5%, n = .015, what is the critical velocity?

Yeah, the CERM doesn't have the neat formula that the AI1 has on page 513 (303.42) but this is how I'd solve it using the CERM (I have the 10th edition CERM so my page numbers may not match other editions). Not sure if this would take less than 6 minutes or not in the heat of battle.

Step 1: CERM Appendix 19.E (10th edition page A-41): Q = K (1/n) d^(8/3) S^.5. Rearrange, solve for d. d = [Q (1/K) n (1/(S^.5))]^(3/8). From the table, K = 2.71 and therefore d = 0.9122 ft

Step 2: CERM Table 19.2 (10th edition page 19-3): A(triangle) = d^2 / tan < theta > (or, A(triangle) = m d^2). Theta = 18.4 degrees and therefore A = 2.50 ft^2

Step 3: CERM equation 19.1 (10th edition page 19-2): Q = V A. Rearrange, solve for V. V = Q / A. V = 4.0 ft/sec

I get 4.0 and Goswami gets 3.9.

Do you guys see any errors in my process?

Edited by ptatohed

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Hmm I think you're on to something. I haven't used Table 19.2 yet but it looks like I should. I like your style. I would not have thought to take your route but it works and that's what counts.

Thanks for sharing.

Jason

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The above comments are right to the point about this book. I too had studied considerably prior to purchasing this book and felt my confidence crushed when I started working the problems. Many of the problems are very specific to Goswami's text book versus having anything relative in CERM. The book contains numerous problems that have no resemblance to the NCEES outline and many of the problems take a lot longer and are much more complicated than could ever be done within 6 minutes and this is applicable to the problems for the two morning exams and the construction depth exam I have worked through. There are some good problems in this book; there are numerous errors; problems not applicable and problems that are way too complicated. However, the book has its good points and does make you think and its complexity is the tough love practice needed preparing for next month's exam.

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ERRATA

Page 195, Problem 36. Should be 243% increase. (not 143%). Unless I'm mistaken.

You are mistaken. If the before and after values had been equal and the ratio had been 1.00, would the % increase be 100%?

Page 37, Problem 120. A lousy question - finding the general relationship for critical velocity/depth for a triangular section. I would like to see if most Civil Hydraulic Professors can solve this inside of 6 minutes? I post this as an Errata because it should be left out of the question set. Maybe a good question for the PM exam, but not AM. Again, 6 minutes.

I believe ptatohed has answered this.

Page 212, Problem 123. I get V = 6.18 ft/sec. I think Goswami's answer (7.15) works too. Might be a bad coincidence of two intersecting solutions.

V = 6.18 ft/sec doesn’t fit the equation

Page 40, Problem 126. Did the Author take time to read the NCEES Breadth syllabus for Transportation? Nowhere do I see traffic counts, studies, of any kind. Therefore, this should be removed from the AM and placed in the Transpo PM problem set.

Every page of the official syllabus has the following fine print – The knowledge areas specified as examples of kinds of knowledge are not exclusive or exhaustive categories.

Page 42, Problem 132. See previous statement. Wasted ink.

See previous statement.

Page 46, Problem 140. Poorly written. Not clear what we are asked to find: net cost of what? Crashing Schedule option vs. Normal Schedulle?

Agreed. The language could definitely have been clearer. As solved, the word ‘net’ implies cost + bonus – penalties for crashing.

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problem 508 from transpo. in the solution he uses equation 404.36 from his book with the spiral angle in degrees. in his book it says to use spiral angle in radians with equation 404.36. Which is it?

AAAARGH!! I'm starting to wonder if I can trust his book at all, and I've been using it instead of the CERM for most of my studying.

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problem 508 from transpo. in the solution he uses equation 404.36 from his book with the spiral angle in degrees. in his book it says to use spiral angle in radians with equation 404.36. Which is it?

AAAARGH!! I'm starting to wonder if I can trust his book at all, and I've been using it instead of the CERM for most of my studying.

benny,

I am nearly certain that spiral curves are not on the exam. Don't waste your time studying topics you won't be tested on. I always skipped the spiral stuff (in CERM, in AI1, in Green Book) and never saw it on the Transpo PM (took twice) nor the CA-Survey.

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problem 508 from transpo. in the solution he uses equation 404.36 from his book with the spiral angle in degrees. in his book it says to use spiral angle in radians with equation 404.36. Which is it?

AAAARGH!! I'm starting to wonder if I can trust his book at all, and I've been using it instead of the CERM for most of my studying.

Equation 404.36 gives "k = xc - Rc sin thetas = Ls(0.5 - qs2/60)"

If you use the sin thetas version, it doesn't matter whether theta is angles or radians as long as your calculator is set to the right mode. If you use the alternate expression, then you theta must be in radians.

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I agree with ptatohed, highly unlikely sprials are on the exam. Stick to the NCEES syllabus. Anything more is wasted effort. 3 weeks left...

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Breadth exam No. 2 - the deflection angle (I) computes to 63.56 degrees using his (and my calculated numbers) - Goswami cites 57.2 degrees ???

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Oops - sorry - Prob. No. 130 (page 215 of text).

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How is the deflection angle equal to 63.56?

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crap - next time check your mode setting (HP 35S) - sorry... Goswami wins!

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Which brings up a good point - we should all know how to change our calculator settings from radians to degrees, visa versa. And shame on us if we don't. What if the batteries fail during the exam and after changing them, we have to change settings back?

thanks,

Jason

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Goswami Depth Prob 404 - (Water Resources) - how is it possible to relate concentration of micrograms per liter to a flowrate in cfs - something dosen't seem right here.. shouldn't we be converting MGD to CFS to flow rates to liters per second since the contamination levels are given in micrograms per liter?? The units don't cancel as you have the 3.094x term where 3.094 represents CFS at the plant.

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.. I could be just losing it.

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Goswami Depth Prob 404 - (Water Resources) - how is it possible to relate concentration of micrograms per liter to a flowrate in cfs - something dosen't seem right here.. shouldn't we be converting MGD to CFS to flow rates to liters per second since the contamination levels are given in micrograms per liter?? The units don't cancel as you have the 3.094x term where 3.094 represents CFS at the plant.

[Q1(cfs) x conc1 (g/L) + Q2(cfs) x conc2 (g/L)]

---------------------------------------------------------- = average conc (g/L)

Q1(cfs) + Q2(cfs)

Units work, what's the problem?

Edited by civilized_naah

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you're right.. a long day

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delta Z for Pump Problem 405 (Depth) on page 106 uses 70' as delta Z - should be 80'

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