Tuesday 3/26/19


Today we looked at what air pressure is.   We first had a demonstration of a pop can being crushed
We then defined what air pressure is according to the book.  Air pressure is the measure of force per unit area with which air particle push on matter. We then took the time to discuss how the following images help to explain air pressure.

     The first image on the left shows that air pressure is like the air in a balloon.  It has to have equal pressure on inside as the outside in order to keep its size.  More inside pressure means a bigger balloon less inside pressure means a smaller balloon.   
   The Second image shows a football that was left out overnight in the late fall.   If the football is brought in to be warmed it will return to its original size.   This shows that heat energy affect pressure.
     The last picture on the right shows that air is a fluid and much like the water in a pool it also has weight. In fact we have about 10 km of air that pushes down on us. 

We then looked at the next image:

Here we talked about how going up and down in elevation will also affect pressure.   The minivan is used to show a family on vacation that goes up a mountain pass and then down to a valley.  This trip will have the kids ear pop because of the change in pressure.


For fun well look at the following videos.