---
title: "The \\( 70 \\) \\( \\text{kg} \\) student in the figure balances a \\( 1200 \\) \\( \\text{kg} \\) elephant on a hydraulic lift. Assume that it is filled with oil, which is incompressible and has a density \\( \\rho = 900 \\) \\( \\text{kg/m}^3 \\). What is the diameter of the piston the student is standing on? Assume each piston has a cylindrical shape, i.e., a circular cross-sectional area. Note: The two pistons are at the same height. Also, the diameter of the wider piston is given in the figure to be \\( 2.0 \\) \\( \\text{m} \\). \\textit{Hint: Refer to your notes on Pascal’s Law and hydraulic lifts which says that the forces are related by:} \\[ \\frac{F_1}{A_1} = \\frac{F_2}{A_2} + \\rho gh \\]"
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url: "https://nerd-notes.com/ubq/81511/"
date_modified: "2025-03-13T11:17:34+00:00"
---

# The \( 70 \) \( \text{kg} \) student in the figure balances a \( 1200 \) \( \text{kg} \) elephant on a hydraulic lift. Assume that it is filled with oil, which is incompressible and has a density \( \rho = 900 \) \( \text{kg/m}^3 \). What is the diameter of the piston the student is standing on? Assume each piston has a cylindrical shape, i.e., a circular cross-sectional area. Note: The two pistons are at the same height. Also, the diameter of the wider piston is given in the figure to be \( 2.0 \) \( \text{m} \). \textit{Hint: Refer to your notes on Pascal’s Law and hydraulic lifts which says that the forces are related by:} \[ \frac{F_1}{A_1} = \frac{F_2}{A_2} + \rho gh \]

The \( 70 \) \( \text{kg} \) student in the figure balances a \( 1200 \) \( \text{kg} \) elephant on a hydraulic lift. Assume that it is filled with oil, which is incompressible and has a density \( \rho = 900 \) \( \text{kg/m}^3 \). What is the diameter of the piston the student is standing on? Assume each piston has a cylindrical shape, i.e., a circular cross-sectional area. Note: The two pistons are at the same height. Also, the diameter of the wider piston is given in the figure to be \( 2.0 \) \( \text{m} \).

![Diagram](https://nerd-notes.com/wp-content/uploads/2025/03/elephantandpersononoppositeendsofpistons.png)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/81511/*