Hello everyone coming from Singularity Hub! Check out my demonstration videos for a good overview of what I’m trying to do. And for the educators out there, take a look at my lesson plans and let me know what you think!
After my last post about the effect of portals on cube velocity, I was asked about the actual velocity limit for cubes moving through portals. It’s easy to calculate. Looking at my Portal Velocity Limit Spreadsheet, it’s clear that any cubes dropped farther than about 8 panels were slowed to the same velocity as they passed through the portals. To get an idea about the portal velocity limit, we’ll start with the equation:
From the spreadsheet, we’ll be using 
Of course, that doesn’t take air resistance into account, so we really just found an average velocity. To find the instantaneous velocity of a cube as it passes through the portals, we’ll be using the console command, “physics_debug_entity.” Check out the video below.
It looks like our results make sense. We would expect the instantaneous velocity of a cube when it first leaves the portal to be higher than its average velocity after being slowed down by air resistance.
Physics with Portals 