Which unit is used to measure pressure?

Pressure is defined as the force applied per unit area. The standard unit of pressure in the International System of Units (SI) is the pascal, which is defined as one newton per square meter. This unit quantifies how much force is exerted over a specific area, thereby providing a measurement of pressure.

Other units mentioned, such as gallons and liters, measure volume and are not relevant to pressure measurement. Amperes measure electric current, which is unrelated to pressure. This makes pascals the correct choice for measuring pressure, as it directly corresponds to the fundamental definition of pressure in physics.