How much PSI is needed to lift a pound?

To lift one pound using air pressure, you need approximately 1 psi. This is based on the principle that 1 psi can lift about 1 pound per square inch of surface area. Therefore, if you have a larger surface area, you would need proportionally less psi to lift the same weight. For example, a surface area of 2 square inches would require only 0.5 psi to lift 1 pound.