Want some #verisimilitude for your post-apocalyptic story? Four years after the pandemic started, 7 out of 7 examined #battery-powered candles had burst batteries. 3 out of 7 had destroyed circuitry and were irreparable. I restored four of the candles to working order with a lot of cleaning and scrubbing, but of course they required fresh #batteries.
Takeaway: Nothing battery-powered left for four years will work when found. Much of it will be destroyed.
Bonus: Gasoline has a shelf life and may be useless in 6-12 months. Sorry, no verisimilitude in Mad Max.
My character's knowledge ends way before my knowledge of the subject ends.
#Fantasy#magic systems often fail to impress because lots of detail, except where the reader can intuit a logical loophole, is a bad thing! The reader will often assume the gaps for you. I must remind myself every so often that a story is entertainment, not a treatise or thesis on speculative science, sociology, or engineering, especially after all time I spent on the research. When I wrote from a prize-fighter's POV, I learned how training felt, and the injuries, but I didn't presume to write the coach working their miracles. Only enough to convince.
I try to be imprecise, even about what I know a subject very well. Well, heck, I recognize I could misunderstand somethng! I then lampshade enough to ensure the story makes sense and to keep the plot logically together. I would, for example, make sure to understand the limits of a submersible pressure vessel (I don't) and get that much right. I'd also work on the jargon. My character would then be passenger told not to touch anything, and not an engineer or pilot.
A tactic I use is to consider secondary characters to provide "details." I include lieutenants, clerks, and engineers to do real work, maybe letting them talk down to the MC because the MC couldn't possibly understand and is wasting their time. This excuses lack of detail.
Everyone is a lay person about something, many many somethings, IRL. To the extent that I don't know how to maintain my car, build my house (I actually did), generate my electricity, butcher my meat (thinking about which turns me into a vegetarian for a few hours), and piloting an airplane, I make my characters the same way. Builds a sense of #Verisimilitude