FE Civil Practice Question Solution included after investigation
CASE E-047 · FE

The Tank Gauge That Read 58.9 kPa at 6 m

The water was motionless, but pressure still increased with depth.

▶ INTERACTIVE CASE FILE • 5–10 MIN • CLICK TO INVESTIGATE

Inspect, commit, prove, fix, and sign off.

Case E-047 engineering failure visual
HOW THIS WORKS

Think like
a real engineer.

Follow the investigation process used in the field — in five guided steps.

1

Inspect

Review the problem, diagram, and evidence.

2

Commit

Choose your hypothesis.

3

Prove

Run calculations and test your idea.

4

Fix

Select and validate a safe correction.

5

Sign Off

See the full debrief and key takeaways.

Case Brief

SAME PRINCIPLES. HIGHER STANDARDS.
PROBLEM STATEMENT

An open water tank has a pressure tap 6 m below the free surface. A technician expects near-zero gauge pressure because the water is stationary. The gauge reads about 58.9 kPa. Calculate the hydrostatic gauge pressure and identify the mistaken assumption.

Fluid Mechanics Hydraulics Civil Design Verification Root Cause Analysis Safe Correction
E-047
INVESTIGATION WORKSPACE WORK THROUGH THE CASE — YOUR CHOICES MATTER.
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DEBRIEF (LOCKED)

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Find the root cause, confirm the fix, and see how this connects to the exam.

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CASE CLOSED · ENGINEERING VERDICT

What actually failed — and what should change.

What failed

Static fluid was incorrectly treated as zero-pressure fluid.

What was missed

The weight of the water column creates a pressure gradient.

Corrected model

Use p=rho g h for gauge pressure below an atmospheric free surface.

QUICK ANSWER

In a static liquid beneath an atmospheric free surface, gauge pressure is p=rho g h. For water at 6 m depth, p=1000×9.81×6=58.86 kPa gauge.

ENGINEERING TAKEAWAY

In a static incompressible liquid, gauge pressure increases with vertical depth according to p=rho g h.

CASE QUESTIONS

Questions this case should settle.

What is water pressure at 6 m depth?

About 58.9 kPa gauge.

Does hydrostatic pressure depend on tank area?

No. At a given depth it depends on fluid density, gravity, and depth.

NEXT FE PRACTICE QUESTION

The Channel That Carried 5.69 Cubic Meters per Second

Fluid Mechanics Hydraulics · 5–10 min

Continue Practice →
WHAT YOU’LL LEARN

Real failures. Lasting skills.

Each case is designed to build the judgment, analysis, and confidence you need for engineering exams — and beyond.

  • Apply core engineering concepts to real-world problems
  • Practice structured troubleshooting and analysis
  • Strengthen exam-ready thinking through realistic scenarios
COMMON QUESTIONS
Do I need prior knowledge to use these cases?

Basic subject familiarity helps, but every case is designed to teach through the investigation itself.

How long does a case take?

Most cases are designed for a focused 5–10 minute investigation.

Are the cases aligned with engineering exams?

Each case is mapped to a verified exam, subject, topic, and misconception before publication.

What happens after I complete a case?

The sealed debrief unlocks with the root cause, corrected reasoning, fix, and takeaway.