Question

Which of the following is/are NOT true?

• A. Air pressure depends on the density of the air, or how close together its molecules are
• B. In cold air, the molecules are more closely packed together than in warm air, so cold air is more dense than warm air
• C. None of the above
• D. Temperature also makes changes in air pressure

Answer 1

Answer: (C)

Air pressure is dependent on the temperature of air. More is the temperature, more is the air pressure and vice-versa. In cold air, the temperature is low and so the molecules of air have less kinetic energy. Due to this, the molecules are more closely packed together than in warmer air and so cold air is more dense than warm air. This also suggests that lesser is the temperature of air, more is the density of air and less is the air pressure. Hence, air pressure also depends on the density of the air.

So, all the statements are true.