Chapter U3.12, Problem 1TAI

Interpretation Introduction

Interpretation: The cause of gas pressure by molecules has to be explained.

Concept introduction: Pressure is defined as the amount of force that acts over one unit of area. It is exerted by one substance over the other substance.

Answer to Problem 1TAI

The force generated per unit area due to imparting of momentum by molecules of gas to walls of container generates pressure.

Explanation of Solution

Molecules of the gas are in constant motion. This motion leads to the pressure over the walls of the container. The molecules of gas are in a free motion. They collide with each other and the walls of the container. The molecules of gas have mass as well as momentum. Thus, when molecules of gas strike with the walls of the container, momentum is imparted to the walls. This generates a force in perpendicular direction. The summation of the forces and their division by area gives the pressure exerted over the wall.

Conclusion

The force generated per unit area due to imparting of momentum by molecules of gas to walls of container generates pressure.