3B Scientific Pascal’s Pressure Sphere User Manual
Operating instructions
2
Operating instructions
3B SCIENTIFIC® PHYSICS
U14325 Pressure propagation device for liquids
1/03 ALF
®
The pressure propagation device for liquids is used to
demonstrate the equal distribution of pressure in all
directions in a liquid.
1. Safety instructions
• Handle the glass vessel carefully to avoid breakage
and resulting injury.
• Exercise particular caution when taking out the pis-
ton in order to avoid breakage.
• Be careful when using coloured water not to let it
splash on your clothes, for example.
2. Description, technical data
The pressure propagation device consists of a piston in
a long glass cylinder which merges at one end into a
glass sphere to which 7 spray nozzles have been fused.
Total length:
Approximately 450 mm
Glass sphere:
Approximately 80 mm Ø
Glass cylinder: Approximately 35 mm Ø
3. Procedure
• Immerse the pressure propagation device fully in a
bucket of water. Push the piston forward to expel
any air bubbles from the glass sphere. If necessary,
turn the device to get rid of the air.
• Pull the piston back slowly to fill the glass sphere
with water.
• Hold the pressure propagation device about 1 m
above a large surface (for instance, the floor)
• Ensure that the nozzles are in a horizontal position.
• Push the piston forward to exert pressure on the
liquid.
• Mark the points at which the water impinges on
the surface.
• These points form a semicircle whose center is lo-
cated beneath the middle of the glass sphere, pro-
viding evidence that the pressure inside a liquid is
propagated equally in all directions.
For a more precise demonstration:
• Fill the glass sphere with coloured water (see above).
• Cover the experimentation table with paper or cel-
lulose.
• Clamp the pressure propagation device carefully on
a tripod.
• Exert a light and uniform pressure on the piston.
• Measure the coloured straight lines drawn by the
emitted water.
3B Scientific GmbH • Rudorffweg 8 • 21031 Hamburg • Germany • www.3bscientific.com • Technical amendments are possible