Atmospheric Pressure (Courtney Carpenter)

Author

Courtney Carpenter

Principle(s) Illustrated

1. Atmospheric pressure (atm)

2. Pounds per square inch

3. Hypothesis

Standards

• ESS2.A: Earth Materials and Systems

• ESS2.D: Weather and Climate

Questioning Script

Prior knowledge & experience:

Students should know that atmospheric air is composed of various elements i.e. oxygen, carbon dioxide, nitrogen, etc and contains mass. Therefore gravity would cause air pressure to be greatest near Earth's surface.

Root question:

Why does stick break when paper is laid over it and doesn't when there is no paper?

Target response:

Atmospheric pressure is great enough to break the stick.

Common Misconceptions:

Air does not consist of matter.

Atmospheric air is empty.

Movie

In this video you see a stick sitting on the edge of a table and another stick under a piece of paper on the edge of the table. When struck the stick under the paper snaps in half while the free stick does not break.

Calculations:

More Advanced Questions:

After I demonstrate I allow students to try it out themselves. I allow them to ask questions, but here are some common questions that I like to discuss afterwards:

1. What happens to pressure when paper is crinkled? smoothed out?

2. Predict what would happen if you were to do this on Mount Everest? (do calculations)

3. Predict what would happen if you were to do this in Death Valley? (do calculations)

4. Predict what would happen if you were to do this in space? (do calculations)

Reference

I heard another science teacher talking about this concept. I figured out the pressure calculations one day in my classroom!