I read your question, and I found it unclear as well. To simply explain:
Imagine you are watching a show on your computer. You're going to have to be a whole lot closer to watch it properly than if it was on a giant, 48" flat-screen TV. Of course, this is a bit of an exaggeration to make a point, but you haven't given any factors for the situation. You give some example parameters, but you don't tell us
- How good your theoretical person's eyes are
- How big your theoretical TV is
- What the pixel size/resolution of the screen is
- etc., etc.
Whatever parameters you want to include. Just saying, "Here are some possible parameters...do whatever you want" means it isn't really possible to get an answer. People might be able to make some vague, generalistic statements (i.e., the bigger the screen the farther away the ideal seat could be) but nothing that makes it a question worth answering, because I find that generalistic statement rather obvious. If you want an equation, you have to list the parameters, and give us a way to measure data/take data. This also kind of covers why it is broad...there are too many ways to answer it without knowing who you've designed this experiment for.
By the way, the box that says "question isn't clear" also says "Please clarify your specific problem or add additional details to highlight exactly what you need." That's exactly what we need...additional detail.
(By the way, I don't see how it really involves physics at all, but that's just me.) Anyway, I hope this helps.