Pressure

What it Shows

An inverted trash can is launched into the air by an exploding bottle of liquid nitrogen.

Link to Liquid Nitrogen Trashcan video can be found here https://harvard.hosted.panopto.com/Panopto/Pages/Viewer.aspx?id=6f33f468-528c-4ab5-acd6...

What it shows:

A liquid in a number of different shaped communicating vessels will find the same level in each.

How it works:

The pressure at the bottom of the fluid depends upon the depth of the fluid and not on the shape of the container. The apparatus...

What it shows:

Three containers are filled with water to the same depth, and each has the same base surface area (see figure 1). Since the pressure and area are the same in each container, the force should be the same (pressure = force/area).

When evacuated, held together by bombardment of atmospheric molecules.

What it shows:

Two brass hemispheres are brought together and evacuated, and are held together by the pressure of the atmosphere.

How it works:

Two brass hemispheres fit together to form...

What it Shows

With an air pressure of 10⁵ Nm^-2 at sea level, even a heavy duty oil drum will be crushed if it has nothing inside to balance the pressure.

Video of our demo in action https://youtu.be/VOSgHIklv6w

How it Works

The screw cap on the drum is...

What it shows:

This is a concept question relating to Pascal's cask-bursting experiment. Imagine the experiment inverted—literally! Attach a 20-ft length of tubing to the opening of a can full of water. Turn the can upside down and raise it high. Will the...

A model of molecular motion and pressure using practice golf balls.

What it shows:

The kinetic energy of gas molecules bouncing off a surface causes pressure.

Increasing the molecules' speeds increases the pressure and the volume of the gas.

How it works:

Pla...

A sealed balloon in a bell-jar "blows up" as the jar is evacuated.

What it shows:

A siphon is a device that allows the transfer of a fluid from one reservoir to a second at a lower level even though the first part of the journey is up-hill.

How it works:

A siphon is effectively an inverted U-tube with unequal length tubes...

What it shows:

Blow up a long cylindrical balloon and it inflates according to Laplace's law. Arteries, which also need to be flexible, are designed to fight against the kind of aneurysms seen in inflating rubber balloons.

How it works:

Laplace's law for...