Free Body Diagrams

This week I’ll be talking about a major scene from A Togahan Returns, so if you haven’t read that yet, and don’t want stuff spoiled….well, I’ll see you next week. Otherwise, follow me past the page break…

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One of my favorite scenes in ATR was when Dante leaped off the bridge to save Sharathana. That rough image -catching someone in midfall- had been in my head for months before I wove it with the rest of the story. While approaching that scene in the rough draft, however, I hesitated. In my original concept, Dante jumped from the smaller peak to save her. But then a thought struck me, in fact woke me right up in the middle of the night in a state of amplified emergency. I keep pen and paper beside my bed to capture these thoughts, and while most mornings they look like a drunken bar receipt signature, in this case, I had written the question, “Can Dante reach her?”

I chewed on that idea for a bit, but that just generated more questions: “Well, how fast is she falling? How tall are the peaks and bridges? How far apart are they?” I needed to answer these before I could answer the big question. These are things that don’t show up in the final manuscript because they’re not necessarily relevant to the story, and shoe-horning them in would have just slowed it down. But they mattered to me, and they mattered to that core question: If Sharathana fell from the higher peak, could Dante travel far enough horizontally, jumping from the lower peak?

Falling back on my engineering education, I drew a free body diagram*:

ATR_FBD_croppedNow, I’m sure I didn’t get the equations 100% correct and some of you can probably find the flaws, but it was enough to give me a ballpark answer: No, if Sharathana fell from the high peak and Dante leaped from the lower peak, he would fall short**.

Dammit.

Maybe most readers wouldn’t have picked up on this, but it would have bothered me regardless. So I took a look at the story and realized that if Dante were able to progress to the higher peak somehow, then he could catch her. And yes, there are probably a dozen other ways I could have no-prized myself out of this inconstancy, but I was shooting for one that felt right with the world and fit right with the story. In the end, it was a gut choice.

I don’t do that type of analysis for every scene, and there are arguably other places where it might have helped, but in this case I was inspired to use it and was satisfied with the result. And hopefully, so were you.

* The numbers here are rough approximations; please don’t interpret them as canon.

**This assumes that Neo’s gravitational constant is similar to Earn’s (which is conveniently equal to Earth’s).  While I could have assumed a different one to provide for the scene I wanted, it would have contradicted the physics…oh, EVERYWHERE ELSE.

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