1
Quiz 8 Report 10/23/2019
1. Summary
0 0
2
0
3 3
2 2
0 0.5 1 1.5 2 2.5 3 3.5
0-3 3-4 4-5 5-6 6-7 7-8 8-9 9-10
Number of Students
Grade
Quiz 8 Grade Distribution
7.67
8.90
7.72
6.93
8.24 7.63
1.60
0.79
1.90 1.47 1.29 1.47
0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00
2019 2018 2017 2016 2015 2014
Grade
Year
Quiz 8 Comparison with Previous Years
Average Standard Deviation Average Over 2014-2019
Total number of students 14
Attended 12
Missed 2
Average grade 7.67
Standard deviation of grades 1.60
2 2. Comments
Many students used wrong boundary condition at 𝑟 = 𝑏
→ It should have Negative sign 𝑉𝑧(𝑏) = −𝑉
Some of students couldn’t neglect the Pressure gradient term or Gravity term.
Several students discretized velocity gradient incorrectly/
Ex) 𝜕
𝜕𝑟(𝑟𝜕𝑉𝑧
𝜕𝑟) → 𝜕𝑉𝑧
𝜕𝑟 + 𝑟𝜕2𝑉𝑧
𝜕𝑟2 But several student did 𝜕
𝜕𝑟(𝑟𝜕𝑉𝑧
𝜕𝑟) → 𝑟𝜕2𝑉𝑧
𝜕𝑟2
One student made mistake about Natural log function as shown in below.
1 ln (𝑎
𝑏)= ln (𝑏
𝑎) → wrong
