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Chapter 11 | Fluid Statics 451
Making Connections: Gas Particles in a Container
Figure 11.7 Gas particles vibrate within a closed container.
Imagine a closed container full of quickly vibrating gas particles. As the particles rapidly move around the container, they will
repeatedly strike each other and the walls of the container.
When the particles strike the walls, a few interesting changes will occur.
Figure 11.8 The figure on the left shows gas particles traveling within a closed container. As the particles travel, they collide with each other and with the container walls. The figure on the right shows an increased number of gas particles within the container, which will result in an increased number of collisions.
Each time the particles strike the walls of this container, they will apply a force to the container walls. An increase in gas particles will result in more collisions, and a greater force will be applied. The increased force will result in an increased pressure on the container walls, as the areas of the container walls remain constant.
Figure 11.9 A force F is placed upon the particles each time they strike the container walls. These forces result in new trajectories, as shown by the red arrows. Because the particles in the figure on the right are moving more quickly, they experience a larger force than those shown in the figure on the left.
If the speed of the particles is increased, then each particle will experience a greater change in momentum when it strikes a