Pressure is typically expressed in which units?

Pressure is typically expressed in various units, depending on the context and the system of measurement being used. One of the most common units for measuring pressure in the imperial system is pounds per square inch (psi). This unit indicates the amount of force (in pounds) applied per square inch of area. It is particularly prevalent in hydraulic and pneumatic systems, where understanding how pressure translates to force exerted by fluids is critical.

The other units mentioned can also represent pressure but serve different purposes or are used in different contexts. For example, the Pascal, which is the SI unit for pressure, is commonly used in scientific and engineering calculations but may not be as familiar in everyday applications. Pounds per square foot is another unit of pressure but is less commonly used than psi in most hydraulic and pneumatic contexts. Grams per cubic centimeter is a unit of density rather than pressure, and therefore wouldn't apply to this question.

Thus, pounds per square inch is the most relevant and widely recognized unit for measuring pressure specifically in the context of hydraulic and pneumatic systems.