The measure of the force with which air molecules are pushing on a surface is called air pressure.

Here's a breakdown:

* Air pressure is the force exerted by the weight of the air above a given area.

* It's caused by the constant collisions of air molecules with the surface.

* The more molecules there are in a given area, the higher the air pressure.

* Air pressure is typically measured in units like pascals (Pa) or atmospheres (atm).

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