Density and pressure
Pressure pad
Compare pressure from a force on an area with pressure from a depth of liquid.
P = F / A
Apparatus
- Loaded pad
- Changeable area
- Column of water
Method
- On the pad, set the force and the area and read the pressure.
- Halve the area and check that the pressure doubles.
- Switch to the liquid column. Set the depth.
- Read P = hρg and notice it does not depend on how wide the column is.
No hazard on the model. A real high-pressure line is not a school experiment.
F = 400 N
Pressure
4000Pa
Force
400N
Area
0.1m²
g
10N/kg
Set-up
P = F / A = 400 / 0.1 = 4000 Pa.
Same force, smaller area, higher pressure. Deeper water, higher pressure.
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