MCQ
We sit in the room with windows open. Then,
  • A
    air pressure on the floor of the room equals the atmospheric pressure but the air pressure on the ceiling is negligible
  • air pressure is nearly the same on the floor, the walls and the ceiling
  • C
    air pressure on the floor equals the weight of the air column inside the room (from floor to ceiling) per unit area
  • D
    air pressure on the walls is zero, since the weight of air acts downward

Answer

Correct option: B.
air pressure is nearly the same on the floor, the walls and the ceiling
b
(b)

Gas molecules move randomly and effect of gravity on them is insignificantly low. So, pressure exerted by gas molecules is same everywhere.

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