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Question
ABCDEFGH is a hollow cube made of an insulator (Figure). Face ABCD has positive charge on it. Inside the cube, we have ionized hydrogen. The usual kinetic theory expression for pressure ______.
- will be valid.
- will not be valid since the ions would experience forces other than due to collisions with the walls.
- will not be valid since collisions with walls would not be elastic.
- will not be valid because isotropy is lost.
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Solution
b and d
Explanation:
According to the problem, ionized hydrogen is present inside the cube, they are having a charge. Now, due to the presence of a positive charge on the surface ABCD hydrogen ions would experience forces other than the forces due to collision with the walls of the container. So, these forces must be of electrostatic nature. Hence, the Isotropy of system is lost at only one face ABCD because of the presence of an external positive charge. The usual expression for pressure on the basis of kinetic theory will be valid.
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