Q. Which among the following statements is/are correct about atmospheric pressure?
  1. The air at the surface is denser and hence has lower pressure
  2. The air pressure is proportional to density as well as temperature
Select the correct code from the options given below:

Answer: Only 2
Notes: Due to the influence of gravity, the air at the surface is denser and hence has higher pressure. A change in either temperature or density will cause a corresponding change in the air pressure. The air pressure is proportional to density as well as temperature.