Atmospheric pressure and my paper

[anthropos]

Hullo, I am a 16-year-old. This is a question in my assignment.

 

A student said that a piece of paper would fall on the ground when released because the atmospheric pressure forced the paper to fall down. Use the kinetic theory to determine whether the above statement is true.

 

So my answer is (Pardon my grammar. i know it's bad)

 

The above statement is false. The volume of fixed mass of air on the upper and lower sufaces of the paper is the same. This means that the number of air molecules moving around per unit volume of space is the same on the top of and below the paper. The frequency of collision between air molecules and the two surfaces of the piece of paper is the same, so equal amount of force is exerted per unit area of the paper for the same period of time. Thus the pressure of the air (atmospheric pressure) on top of and below the paper is the same. Unless the pressure on either side of the paper of the air is higher than that of the other side will the paper be forced to move in a certain direction which is impossible in reality, because atmopsheric pressure is generally constant. The real reason why a piece of paper would fall on the ground is because of gravitational force pulling towards the ground.

 

Is the statement true? Is my explanation correct? Please tell me to edit parts which you think that is wrong or could have been better. Just that. Thanks.

[Cap'n Refsmmat]

In theory, the atmospheric pressure above the paper would be a tiny bit less, simply because it's farther up (as altitude increases, pressure decreases). But that's the opposite of what would be necessary, so you're definitely on the right track.

[anthropos]

HURRAY! Woots! Thanks a lot. captain.