---
title: "A student monitors the gauge pressure at the bottom of a cylinder filled with water. If the student pours out half of the water and replaces it with an equal volume of oil (which is less dense than water and does not mix), how does the gauge pressure at the bottom change?"
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url: "https://nerd-notes.com/ubq/107059/"
date_modified: "2026-08-18T02:38:39+00:00"
---

# A student monitors the gauge pressure at the bottom of a cylinder filled with water. If the student pours out half of the water and replaces it with an equal volume of oil (which is less dense than water and does not mix), how does the gauge pressure at the bottom change?

A student monitors the gauge pressure at the bottom of a cylinder filled with water. If the student pours out half of the water and replaces it with an equal volume of oil (which is less dense than water and does not mix), how does the gauge pressure at the bottom change?

- **A.** The gauge pressure remains the same because the total volume is constant.
- **B.** The gauge pressure decreases.
- **C.** The gauge pressure becomes \( 0 \) because oil is not water.
- **D.** The gauge pressure increases.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/107059/*