I can’t help myself. When I see someone using physics in a show, I feel compelled to analyze it. In this case, it’s from HBO’s Silicon Valley season 2. Let me get you up to speed.
Gilfoyle and Dinesh are working to set up a live stream of a car jump stunt (piloted by Blaine). It seems that the stunt consists of a special car using a ramp to jump from the roof of one building to the next (the second building is higher). Gilfoyle and Dinesh see his calculations (you can see my sketch above) and try to point out an error (Blaine doesn’t want to hear it). The rest of their conversation goes like this (you can see this clip here):
Dinesh: Hey, you see what I saw?
Gilfoyle: Yeah, I saw. He’s got the velocity calculated wrong. It’s for a flat plane. He doesn’t account for the curve in the ramp.
Dinesh: Exactly. He’s probably used to doing straight ramps. I mean, the chart says he’s gonna launch at 81 mph, but it’s going to be more like…under 70.
Gilfoyle: The downforce is ridiculous.
Dinesh: He’s gonna lose speed and hit the side of that wall — and die….so we should probably….
Gilfoyle: OK, alright.
There’s also a quick view of another board with calculations. It looks something like this (I again tried to reproduce it).
As a science communicator and technical consultant (for MacGyver) I have worked on visual equations like this and I know it can be tough. There are clearly some problems with it, but in this case it’s not supposed to be a perfect calculation (but I will give my analysis of the equations at the end). Instead let me start off with the correct physics and then we can discuss Gilfoyle and Dinesh’s ideas.
Car Jump as Projectile Motion
There’s a bunch of extra stuff in the calculations shown, so let me get to just the essential problem. A car is going to be launched with some initial velocity at a 20 degree angle. It needs to land on another building roof that is 140 feet away…