i have noticed when some one has asked a sensible question they get slated as if they should know?

I see that sometimes too. You get it on all forums, unfortunately.

Another forum I "inhabit" has a lovely phrase on online etiquette, "There is no such thing as a stupid question, and courtesy costs nothing".

I always try to remember that, once upon a time, I didn't know anywhere near as much about things as I do now, and that I am still learning.

Mind you, I do still find it hard to resist the more obvious "trolls". I just try to make my replies such that the troll doesn't realise they are being insulted and everyone else finds them entertaining.