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Air/Water Mortar

It is proposed to construct a mortar to shoot water vertically. It is intended that water be the "projectile." The air compressed beneath the piston will be the "propellant." The figure shows the steps required to "load" the mortar. We will analyze the "loading" and subsequent of "firing" of the motar.

(1) Initiation: A piston is inserted into the cylinder and located to trap 1 cubic meter of atmospheric air beneath it. This air is the propellant. Cylinder dimensions are indicated.

(2) Charging: By a means unspecified, the piston is force downward to compress the air to a pressure of 500kPa. A pin is then inserted to constrain the piston and air.

(3) Loading: Piston in position, water in the amount of 1000 kilograms is placed upon the piston.

The pressure and temperature of the surrounding atmosphere are constantly 100kPa and 300K respectively.

Regarding configuration (2).