If you've blown up a balloon, pumped up a bike tire or used a vacuum cleaner you already have a lot of experience with pressure.
Pressure is the amount of force exerted by a fluid on a surface per unit of area. If the air pressure in a bike tire is 50 psi (pounds / square inch) then each square inch of the rubber inside the tire is experiencing 50 pounds of force (about 222 Newtons). And if we increase the pressure in any part of an enclosed fluid, the pressure increases by the same amount everywhere (known as Pascal's principle).
We're going to talk about atmospheric pressure (the air pressure around us) and the difference between absolute pressure and gauge pressure.
Finally, we'll learn how to describe the pressure in a fluid at different points, and how fluid pressure increases with depth due to the weight of the fluid above it.
Answers
Free-Response Questions
Fluids (previously in AP Physics 2)
Note: These are questions from AP Physics 2 exams before 2025. For some questions only parts of the question are relevant to the Fluids unit in AP Physics 1 as noted below.
Under Pressure (PhET)
Shawn Templin, Louis Wong
Lab 1 - Upside Down Glass of Water
drinking glass, water, index card/cardstock
Cool Science Experiments HQ
Lab 2 - Soda Can Crusher
empty soda cans, stove, tongs, bowl, ice, water
Steve Spangler
Lab 1 - A simple manometer demo
u-tube manometer, syringe, water
MrGrodskiChemistry
Lab 2 - Syringe hydraulic system
2 syringes with different diameters, connecting tube, water
Rhett Allain
If you've blown up a balloon, pumped up a bike tire or used a vacuum cleaner you already have a lot of experience with pressure.
Pressure is the amount of force exerted by a fluid on a surface per unit of area. If the air pressure in a bike tire is 50 psi (pounds / square inch) then each square inch of the rubber inside the tire is experiencing 50 pounds of force (about 222 Newtons). And if we increase the pressure in any part of an enclosed fluid, the pressure increases by the same amount everywhere (known as Pascal's principle).
We're going to talk about atmospheric pressure (the air pressure around us) and the difference between absolute pressure and gauge pressure.
Finally, we'll learn how to describe the pressure in a fluid at different points, and how fluid pressure increases with depth due to the weight of the fluid above it.
