At the ocean's surface, the pressure equals the pressure of the atmosphere above it, normally 14.7 pounds per square inch (101 kPa).
If you open the valve on the tyre, air flows out until the pressure inside the tyre equals that outside.
Replies: Scott, Maximum velocity is the point at which aerodynamic pressure on a falling object equals it's weight.
In fact it does collapse until the pressure inside equals the pressure outside.
For example, a pump delivers 180 lit/min and the pressure equals 250 bar, therefore the power of the pump is 75 kW.
In open vessels the internal pressure of the system equals the external pressure, which is, as we have seen, usually the atmospheric pressure.
When submerged, the ballast tanks are flooded and the inside pressure equals the pressure of the surrounding water.
The final pressure almost equals the partial pressure of helium in air.
Hydrogen is pumped in to fill up the jar so that the pressure inside equals atmospheric pressure.
When the pressure in the airlock equaled that in the ship, the inner lock opened automatically.