VAPOR PRESSURE is the pressure exerted by a vapor confined within a given space. The vapor may be the sole occupant of the space, or may be associated with other gases. VOLUME (See Specific Volume). VOLUMETRIC EFFICIENCY is the ratio in percent of the actual delivered capacity (measured at inlet temperature, pressure and gas composition) to the piston displacement. WET-BULB TEMPERATURE is used in psychrometry and is the temperature recorded by a thermometer whose bulb has been covered with a wetted wick and whirled on a sling psychrometer. Taken together with the dry-bulb temperature, it permits
determination of the relative humidity of the atmosphere. WET GAS is any gas or gas mixture in which one or more of the constituents is at its saturated vapor pressure. The constituent at saturation pressure may or may not be water vapor. WORK is energy in transition and is defined in units of Force times Distance. Work cannot be done unless there is movement. | 
