This page is for your eyes only. The example and practice problems all require Excel to solve multiple, coupled, non-linear, algebraic equations. But it would be a logistical nightmare to include Excel solutions in an exam. Besides, they take a long time to set up and a student (or you!) can get hung up on a simple error in programming. So, how did I examine the student's abilities?
I generally asked two types of questions. One was to perform parts a, b, and c in the solution procedure but stopping after writing the equations as they would be entered into Excel. The other was to interpret results, usually given in graphical form (xy and Txy diagrams). Usually, I guided the student (a. Draw a PFD, b. Conduct a DOF analysis, c. Write the equations ...) That breaks up the problem into manageable pieces for the students, is exactly how we solved problems in class and homework, and makes grading the exams much easier.
Some exams contain topics that I no longer cover. For instance, some algebraic techniques like the Rachford-Rice equation for multiple components or the HTU-NTU method using mass transport. Particularly, most students never really understand the mass transfer methods and they have limited use in industrial practice. Maybe some day ...
Be sure to take your exam yourself and go through all the motions. If it takes you more than 20 minutes, it might be too long. There are two ways to make sure an exam provides a grade distribution. You can make it time limited or you can make it tricky. I go for time limited. Only the best students can finish the exam early (although they are the types that will still linger until time is up, making sure they are 100% correct!). Maybe, three quarters of the students finish the exam and the rest can't complete it. The latter might still pass the exam. But if they fail (and that happens a lot in the first exam) they are allowed to drop one of the four semester exams. I allowed the students to skip the final if they were satisfied with their grade. Alternatively, they could take the final exam and decide on the spot to count it or not. My rule was that if I had to grade their final, it counted, even if it turned out to be their lowest grade. Well, I usually dropped it anyway (I'm a softie) but don't tell them that!
So, below are some examples that I fished out of the deep recesses of my computer. Don't use any question that you haven't thoroughly checked out and have "covered" it in class and practice problems.
I generally asked two types of questions. One was to perform parts a, b, and c in the solution procedure but stopping after writing the equations as they would be entered into Excel. The other was to interpret results, usually given in graphical form (xy and Txy diagrams). Usually, I guided the student (a. Draw a PFD, b. Conduct a DOF analysis, c. Write the equations ...) That breaks up the problem into manageable pieces for the students, is exactly how we solved problems in class and homework, and makes grading the exams much easier.
Some exams contain topics that I no longer cover. For instance, some algebraic techniques like the Rachford-Rice equation for multiple components or the HTU-NTU method using mass transport. Particularly, most students never really understand the mass transfer methods and they have limited use in industrial practice. Maybe some day ...
Be sure to take your exam yourself and go through all the motions. If it takes you more than 20 minutes, it might be too long. There are two ways to make sure an exam provides a grade distribution. You can make it time limited or you can make it tricky. I go for time limited. Only the best students can finish the exam early (although they are the types that will still linger until time is up, making sure they are 100% correct!). Maybe, three quarters of the students finish the exam and the rest can't complete it. The latter might still pass the exam. But if they fail (and that happens a lot in the first exam) they are allowed to drop one of the four semester exams. I allowed the students to skip the final if they were satisfied with their grade. Alternatively, they could take the final exam and decide on the spot to count it or not. My rule was that if I had to grade their final, it counted, even if it turned out to be their lowest grade. Well, I usually dropped it anyway (I'm a softie) but don't tell them that!
So, below are some examples that I fished out of the deep recesses of my computer. Don't use any question that you haven't thoroughly checked out and have "covered" it in class and practice problems.
