TFS · Practice Exam 1 · Problem 24 PDF Solution in PDF ↓
TFS · Practice Exam 1 · Problem 24
Problem & Solution
PDF: Practice Exam #1-24.pdf
Video Synthesis
  • - Problem: Air enters a compressor at 80 degrees and 14.7 PSIA and exits at 180 PSIA.
  • - Approach: One was to make the assumption that it's isentropic and then as long as you're given the inlet temperature you can use the constant entropy process, equations, figure out what the ...
  • - Key values: 14.7 PSIA, 180 PSIA, 129 BTU, 16.97 in
  • - Reference: reference handbook
  • - ✅ Answer: B
Office Hours 1
Student questions asked in live office hours about this problem
OH 81
Q: For TFS Practice Exam #1 Q24, I solved a compressor problem assuming it was isentropic using the constant-Cp formula and delta-H methods, and both gave matching answers—but the problem didn't state it was isentropic, so was my approach wrong?
A: You're right to catch that—there are three ways to solve compressor problems: isentropic formula, delta-H/Cp-delta-T, and air tables. Since the problem didn't specify isentropic, you needed the air table method, which is trickier but important to practice. If isentropic is explicitly stated, the easier methods apply, but knowing the air table approach is essential for the exam.
MPEP OH Prep Dashboard Problem 24 · Practice Exam 1 PDF-Embedded Format