Question: how much does 1 psi weight?
Answer: psi = pounds per square inch. One pound applied to one square inch produces the pressure of 1 pci. The same weight (1 pound) applied to 2 square inches produces twice less pressure -- 0.5 pci. So your 10 psi could be produced by 10 lbs weight applied to 1 square inch or 1 pound applied to 0.1 square inch.