Some people (you know who you are) made me watch Rick and Morty. It can be somewhat extreme, but I can’t look away. Well, you know what happens next, right? I have to apply some physics to something from this show. In particular, let’s look at floating Jerry from the episode Rattlestar Ricklactica.

At the beginning, Jerry falls off the roof of his house and is saved by Rick who makes it so that he floats instead of falls with some type of “ray gun” (even though Jerry doesn’t want a “ray”). Here’s his short explanation.

“I made your atomic matrix SLIGHTLY lighter than air”

So, Jerry would just float away — but wait! Rick then makes his shoes “heavier than air” which makes Jerry neutrally buoyant. Or does it? Maybe — maybe not. OK, there’s a bunch of physics so let’s get started.

The Buoyancy Force

I always have trouble spelling that for some reason. OK, here is your super short explanation of this force from the air (the buoyancy force).

Imagine that you have a box of air floating in air (with no walls). Of course air floats — it has to float or all the air would just end up on the ground (that would be both weird and awkward). Suppose this box of air has a volume V and the density of the air is ρ-air…