Oh, wow, oh, oh, oh, wow, oh, oh, man.

Oh, my. Hello, you're listening to the Science of Everything podcast, episode 40, buoyancy and fluid dynamics.

And I'm your host, James Fodor.

In this episode, we're going to look at the behavior of fluids, particularly fluids in motion, hence fluid mechanics.

We'll talk about fluid pressure, Pascal's principle, barometers, and we'll also look at Bernoulli's equation and some

misapplications of Bernoulli's equation, and particularly how it's misused to explain

how aeroplanes fly. We'll also look at buoyancy, that is why objects float and explain

Archimedes principle. Recommended prerequisites for this episode, episode 13 on Newtonian

mechanics, and episode 27, inter 27 into molecular bonds and phase transitions.

All right, let's get started. First of all, some basic definitions.

Volume refers to the amount of three-dimensional space that's taken up by a substance or an object.

So volume is measured in something like meters cubed or liters. Density refers to the mass of an object

divided by its volume, or in other words, it's the mass per unit volume. Pressensity refers to the mass of an object divided by its volume, or in other words,

it's the mass per unit volume. Pressure refers to the force divided by surface area, or the force

per unit area, where the force is directed perpendicular to the area. So if I press a pin on a

tabletop with my thumb, that will have a relatively high pressure, because although my force

is fairly small, it's just the force of the thumb bush, the area of

between the table and the pin is very small, so my force is large, my area is small, so my force divided by area is large, hence my pressure is large.

Similarly, if I have a very large mass confined in a very small space, my density will be very high.

These concepts are fairly basic and you probably know them, but I just wanted to make sure that they were clear because they're going to be used frequently throughout the rest of the episode.

Now, moving on from basic definitions to a recap on what we mean by solids and fluids and the

difference between them. Now, we talked about this in episode 27, but just a brief

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