How is pressure defined in a scientific context?

Pressure in a scientific context is defined as the force exerted by a gas on a surface per unit area. When a gas molecules collide with the walls of a container or any surface, they exert a force on that surface. The pressure is calculated by taking the total force exerted by these gas molecules and dividing it by the area over which the force is distributed. Thus, pressure is directly related to both the amount of gas and the temperature; increasing either can increase the pressure if the volume remains constant.

Understanding pressure is crucial in various scientific fields, including physics, chemistry, and engineering, as it explains phenomena such as why balloons expand when filled with air, how weather patterns are formed, and how engines operate.