The unit 'Pascal' measures what physical quantity?

The Pascal is a unit used to measure pressure in the International System of Units (SI). It is defined as one newton per square meter, which quantifies the force applied per unit area. This makes it a critical unit in various scientific fields, particularly in physics and engineering, where understanding the behavior of gases, liquids, and solids under different pressure conditions is essential.

Pressure itself is a measure of the external force exerted on a surface in a perpendicular direction, so when we describe pressure in Pascals, we are communicating how much force is being applied over a defined area. In many applications, such as hydraulics, meteorology, and even biology (like blood pressure), pressure's measurement in Pascals is vital for accurate data and analysis.

This unit is distinct from the other choices, which relate to different physical quantities: electric current is measured in amperes, temperature in degrees Celsius or Kelvin, and heat in joules or calories – each of which represents a different aspect of physical phenomena.