question_answer 23)

                  ABCDEFGH is a hollow cube made of an insulator (fig.) Face ABCD has positive charge on it. Inside the cube, we have ionizied hydrogen. The usual kinetic theory expression for pressure. (a) will be valid.                 (b) will not be valid since the ions would experience forces other than due to collisions with the walls. (c) Will not be valid since collisions with walls would not be elastic. (d) Will not be valid because isotropy is lost.

Answer:

                  (b, d) \[P=\,\frac{1}{2}\,\rho {{c}^{2}}\] is valid if the collision between molecules of gas and walls of the container is elastic and no other force exerts.