Joints and Cavitation Lab

How the model works: before a cavity forms, separation rises with force at about 1 mm per 100 N. Separating the sealed joint lowers the fluid pressure, while the capsule and fluid slowly adjust (a time constant of about 1.5 seconds), so a quick pull drops the pressure further than a slow one. When the pressure falls about 6 kPa below its resting level, a gas cavity forms, the pull force dips for an instant and the surfaces jump apart; after that the joint separates easily. The gas dissolves back over about 20 minutes, and until then no new cavity can form. Simplified for learning; real joints and people vary.

For predict then watch items, make your prediction first; the picture then plays out what happens. For numbers, the worked solution builds step by step, with units that cancel struck out in red. All values are rounded teaching values.