The Physics of Ezra and Sabine’s Force Jump

Rhett Allain
7 min readOct 30, 2023
Video Analysis of Ezra and Sabine’s Force Jump using Tracker Video Analysis. Scene from Disney Plus.

I’m not going to give away too many details, but there’s a cool scene in Ahsoka Epsiode 8. The basic idea is that Ezra is trying to make a jump into the bay of a Star Destroyer. Of course he can use the force to get a longer jump — but it’s just not enough. So, he gets a force boost from Sabine who is still on the landing platform.

That’s all the info you are going to get (but let’s be honest — if you haven’t watched Ahsoka yet, then you probably aren’t concerned with spoilers). But here’s what I like about this move. The episode gives this great view from the side. It’s like perfect for video analysis. Of course that’s just what I’m going to do.

Video Analysis of Ezra’s Force Jump

With video analysis, you can mark the location of an object in each frame of the video. If you know the “size” of the frame (pixel to meter conversion) and the time between frames (from the frame rate) then you get x,y, and t data. Nice.

In this video, the camera is looking perpendicular to the motion so that Ezra is at the same distance away (so we don’t have to worry about motion in that direction). Also, the camera doesn’t pan or zoom — which just makes everything easier.

There is one big problem — I don’t know the distance scale of the video. However, if I assume this is projectile motion (constant vertical acceleration) then I need two of the following three things:

  • Distance scale (I don’t have this).
  • Time scale (I’m going to assume the frame rate is in “real time”).
  • Vertical acceleration — I technically don’t know this.

So, here’s what I’m going to do. I am going to assume that during the first part of the motion the only force on Ezra is the downward pulling gravitational force. Wait, here comes the crazy part — I will assume that the gravitational field (which would be the vertical acceleration) is 9.8 Newtons per kilogram. Yes, this the gravitational field on the surface of the Earth and this is a WHOLE DIFFERENT PLANET CALLED PERIDEA. I know that it’s crazy to make this assumption, but I don’t really have any other way to estimate the gravitational field. Anyway, when people move around they look like they are moving on Earth so it…

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Rhett Allain

Physics faculty, science blogger of all things geek. Technical Consultant for CBS MacGyver and MythBusters. WIRED blogger.