Pro 🔒~20 min

Pressure Lab

Explore atmospheric and fluid pressure

How it works

Pressure in a fluid increases with depth: P = P₀ + ρgh. Pascal's Principle states that pressure applied to a confined fluid transmits undiminished in all directions — the basis for hydraulic systems. Atmospheric pressure at sea level is ~101.3 kPa, decreasing with altitude. Bernoulli's Equation shows the trade-off between pressure, kinetic energy, and height in flowing fluids.

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Step-by-step

  1. Drag the pressure gauge to different depths to measure absolute and gauge pressure.
  2. Use the hydraulic press to demonstrate Pascal's Principle — apply small force on small piston, observe large force on large piston.
  3. Check the atmosphere panel to see pressure vs. altitude.

Key formulas

  • P=P0+ρghP = P_0 + \rho g hFluid pressure at depth h
  • P1A1=P2A2P_1 A_1 = P_2 A_2Pascal's Principle (hydraulic lever)
  • P+12ρv2+ρgh=constP + \frac{1}{2}\rho v^2 + \rho g h = \text{const}Bernoulli's Equation

Frequently asked questions

What is the gauge pressure at 10m depth in water (ρ=1000 kg/m³)?
P_gauge = ρgh = 1000 × 9.8 × 10 = 98,000 Pa ≈ 0.97 atm.
A hydraulic press has A₁=5cm² and A₂=500cm². If F₁=100N, what is F₂?
Pascal: P = F₁/A₁ = F₂/A₂ → F₂ = F₁×(A₂/A₁) = 100×100 = 10,000N.
Why does water flow faster through a narrow pipe than a wide one (same pressure)?
Bernoulli: if v increases, P decreases; continuity A₁v₁ = A₂v₂ forces higher v in narrow section.