---
title: "An ideal fluid flows through a horizontal pipe that constricts from a diameter \\( D \\) to a diameter \\( \\dfrac{D}{2} \\). If the fluid speed in the wider section is \\( v_{1} \\) and the pressure is \\( P_{1} \\), what is the pressure \\( P_{2} \\) in the narrower section in terms of the fluid density \\( \\rho \\)?"
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url: "https://nerd-notes.com/ubq/107164/"
date_modified: "2026-08-18T02:38:19+00:00"
---

# An ideal fluid flows through a horizontal pipe that constricts from a diameter \( D \) to a diameter \( \dfrac{D}{2} \). If the fluid speed in the wider section is \( v_{1} \) and the pressure is \( P_{1} \), what is the pressure \( P_{2} \) in the narrower section in terms of the fluid density \( \rho \)?

An ideal fluid flows through a horizontal pipe that constricts from a diameter \( D \) to a diameter \( \dfrac{D}{2} \). If the fluid speed in the wider section is \( v_{1} \) and the pressure is \( P_{1} \), what is the pressure \( P_{2} \) in the narrower section in terms of the fluid density \( \rho \)?

- **A.** \( P_{1} \) \( – \) \( \dfrac{15}{2} \rho v_{1}^{2} \)
- **B.** \( P_{1} \) \( – \) \( 15 \rho v_{1}^{2} \)
- **C.** \( P_{1} \) \( – \) \( \dfrac{1}{2} \rho v_{1}^{2} \)
- **D.** \( P_{1} \) \( – \) \( \dfrac{3}{2} \rho v_{1}^{2} \)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/107164/*