Dog Running on a Stand -up Paddleboard — Physics Breakdown

Rhett Allain
7 min readSep 4, 2021
Photo: Rhett Allain. Dog on a Stand-up Paddleboard

I saw this great video on reddit. It shows an incident with a dog on a stand-up paddle board. I’m going to go over all the cool physics things that you can see here. Let’s get to it.

The first step is to get some data. I’m going to load this video into my favorite video analysis program — Tracker Video Analysis (it’s free). The basic idea is to mark the location of objects in each frame of the video. This will give position and time data. The time values come from the video frame rate, however the position data needs some type of scale to get the pixel-to-distance conversion. I’m going to assume the SUP (that’s what cool people call a stand-up paddleboard) is 10 feet long (that seems fairly common).

Video Analysis

Of course, there is one other thing to consider. The camera view moves around, so I need to mark some location to act as the origin. The woman standing in the water seems fairly stationary, so I will use her along with the horizon to correct for the camera motion. Here is what the stable view would look like.

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Rhett Allain

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