The pressure exerted by a gas on the walls of its container acts in all directions because gas molecules move randomly and constantly in all directions. These molecules collide with the walls of the container from every angle, and each collision exerts a force perpendicular to the surface of the wall. Since the collisions are random and occur evenly throughout the container, the force (pressure) is distributed uniformly and acts in all directions on the container walls. This behavior happens due to several factors:
- Gas molecules have high kinetic energy and are in constant, random motion.
- They are spaced far apart with very weak intermolecular forces, allowing free movement in all directions.
- When the molecules hit the walls of the container, they transfer momentum, exerting force on the container in every direction.
- Pressure is defined as force per unit area and, being a scalar quantity, it has magnitude but no particular direction, so it acts equally in all directions inside the gas.
Thus, the gas pressure is isotropic (equal in all directions) because of the molecular nature of gases and their random motion causing collisions with the container walls from all sides.
