Bell jar: pressure and ventilation sim
Pulling the rubber sheet down increases the enclosed space.
Bell jar · pressure and ventilation · covers the GCSE, IGCSE, O-Level topic
What the sim shows
Pulling the rubber sheet down increases the enclosed space. Pressure falls and air enters the two balloons through the open Y-tube. Moving the sheet back reverses the effect. This is an apparatus model of ventilation: the rigid jar and flat sheet do not reproduce a rib cage or the curved diaphragm.
- The inset shows the rubber sheet and balloons. The model keeps jar air at constant temperature, conserves trapped gas and uses a declared linear balloon compliance. Blocking the Y-tube also traps the original balloon gas.
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