Wait a minute. If you don't know someone's name, are you really going to be using ты to them?
That seemed strange to me too, and it would be interesting to hear a native's opinion. I guess, though, that it would at least make sense to say it to a child.
You're almost right. It makes sense to say it to a child, to contemporary (in informal atmosphere), also to a human who is just much younger (again in informal atmosphere).
If you don't know a person it would be "Здравствуйте, вы Иван?"
Well, it all depends on the context. Say he's one of your best friend's best very good friend and you have been hearing from him for a long time. Another context in which I can imagine such an asking is if they know each other only through the Internet and have never met personally. But I'm just throwing theories into the air.
"Ты" можно говрить на улице, если ты взрослый и обращаешся к ребенку или как минимум к своему ровеснику. Если ты на телевидении или официальное лицо, то обращаешся на "Вы"
Does anyone know if the way the recording sounds is actually how one would express a question. If you were not really listening to someone and you heard this, would you know you had been asked a question?
The inflection is more subtle than beginners might expect, want, or need, but it definitely sounds like a question. A statement would end on a much lower pitch. Also, it would be weird to say hi to someone you recognize and make an exclamation about their identity...
"Hi, you're Mom!"
I said, "Hi, are you Ivan" because Vanya is a diminutive form of Ivan, but it wasn't accepted
If you already know that someone likes to be called Vanya it is not common to use their other more formal name.
unless a child is saying this, this doesnt make sense to me. if you dont know this persons name you would use "вы", right?