Science Basics: Pressure

Introduction

Pressure Ulcers

Measurement

Blood Pressure

Units

Boyle's Law

Activity

Assessment

Resources

Feedback

Units

Other units of pressure are also used. The SI unit of area is the square metre (m²) and the Newton is the unit of force. Since we have defined pressure as force per unit area we can measure pressure in terms of newtons per square metre (Nm^-2), a unit renamed the pascal (Pa) in honour of the french scientist.

For example, if a force of 2 Newtons were exerted over an area of 4m², the pressure applied would be 0.5 Pa. The pascal is actually a very small unit of pressure so in nursing we use a unit of a thousand pascals - the kilopascal (kPa).